Question about Lenses and F/stop #

Discussion in 'Digital Photography' started by disdat, Jul 4, 2007.

  1. disdat macrumors regular

    disdat

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    Jul 21, 2005
    Location:
    New England USA
    #1
    Please forgive me if this is a stupid question. I am still a newbie concerning manual photography.

    I am thinking about purchasing my first dSLR and I have a question or two

    1. When choosing lenses, I have noticed that each lens has what I assume is a max F/Stop # with it. When connected to my camera, will the camera just 'know' that only a certain level of aperture can be used, or if I choose a lower F/Stop than the lens allows, what happens?

    2. I am struggling with the choice between the Canon XT and the XTi. I would love to save $200 and purchase the older XT, so I can put the $ toward lens purchases. But now I am nervous about dust, and perhaps I should go for the XTi. I live in a house with hard wood floors, and forced hot air heat, and this place seems to have a never ending supply of dust. What do you all think?

    Thank you very much for any helpful advice. I am a long time MacRumors lurker, so I don't post often, but I read everyday! ;)
     
  2. Lovesong macrumors 65816

    Lovesong

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    #2
    Hey disdat-

    When using SLR cameras (ones that are not fully manual), the camera and the lens communicate using connectors on the lens and the lens mount. Essentially the camera knows what lens it is that you have on there, and when adjusting the aperture, it will open up only to the maximum of the lens. When using manual SLRs (like the FM 10, or one of those older Canons), the aperture is controlled on the actual lens, so you basically have the option of what that will allow. This also applies when using chop-job lenses on autofocus cameras (by that I mean the people that use multi-thousand dollar Leica and Zeiss glass, so that they can show off the corner sharpness of their pictures~ don't worry about it), which once again will require you to use on the lens manual aperture adjustment.

    Now, for the XT vs. XTi question... if I were shoping for an entry level dSLR, and had settled on the Canon brand (I currently shoot a 5D), I would go for the XT without a hesitation. First off, the XT was 8.1MP, which is more than enough for most everything that I would use the camera for. The XTi jams another 2 MP into the same size sensor, which leads to intrinsically noisier images (this is just physics- more sensors, less space, more noise). Moreover, the anti-dust cleaning thing that Canon used in the XTi, will not solve all of your dust issues. Dust will get on the sensor!!!! Period. There is nothing one can do, except learn to live with it, and eventually learn to clean it (there was a post about it started by Plymothbreezer yesterday). Last, but certainly not least, as any photographer will tell you- don't worry about the body of an SLR system, worry about the glass. When you buy an SLR by a certain manifacturer, you're buying into that company's system, and unless you have a ton of disposable income, you won't be switching back from that system in the near future. That XT or XTi will probably last 10, 15, maybe 20 thousand shutter closures, and will then stop working. At that time you will be left with all the glass you have purchased for the camera, and unless you want to take a large hit on the investment you have made, you will get the next model by the same manifacturer. The lenses are indeed what make the pictures in SLR photography, so invest in those, and you will likely keep them for a long while. In terms of dust, given your living situation, get yourself an arctic butterfly right off the bat. For the smaller cameras, they will run you about $50, and will work much better than the dust reduction system in the XTi. Hope this helps.
     
  3. miloblithe macrumors 68020

    miloblithe

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    #3
    To answer your first question, on Canons, the camera just knows what the maximum f-stop is. For example, on my 24-70 f/2.8, if I try to spin the control dial to set an aperture wider than f/2.8, nothing happens. With my 50mm f/1.8, same thing. If I try to go down to f/1.6 or something, nothing happens. If I spin the control dial the other way, up we go to 2.0.

    As for the XT vrs XTi choice, what is your overall budget. That's an important part of your decision. I chose to get the XTi over the XT and over the Nikon D50 while getting a Canon 50mm f/1.8 ($70) and a Tokina 19-35 f/3.5-4.5 ($130), filters to protect those lenses ($50?, how I was raised), and a 1GB memory card (now like $20). I also had access to a free hand-me-down Tamron 70-210 f/4.5-5.6. So that was about $300 over the price of the camera alone, including shipping, for my starter kit.

    I've since added a camera bag and another 1GB card (another $70 or so), a Bogen/Manfrotto tripod ($250 -- overspent on the tripod, but I figured it'd last me decades), a somewhat unexpected lucky find on ebay (Sigma 24-70 f/2.8 with polarizing filter and skylight filter) ($200), and I just ordered a Canon 430EX flash ($230).

    I still want another CF card and a battery grip with extra battery. That'll take me well over $2000 for my total cost for gear. It adds up quickly.

    So, if you think you're content with what you can afford with the XTi and can wait for later for the things you can't currently afford, get the XTi. If your overall budget is low and you don't plan on getting much else with the next year or so, get the XT. Lenses are more important than the camera, especially in the long run when you've purchased a new camera body (I'm hoping not within 10 years, but I'm an optimist) and the lenses keep going. On the other hand, great lenses tend to be outside of the budget for a lot of people. That's why I bought two lenses that were consistently described as excellent lenses for how cheap they are (the 50mm f/1.8 and the Tokina). Sure the 17-40 f/4 and 50mm f/1.4 are better, but for $900 vrs $200 for the two lenses, weren't an option for me.

    Finally, from dpreview, the difference between the XT and XTi

    10.1 megapixel CMOS sensor with improved microlens array, fill factor and lower noise (which is a minimal difference in most practical applications)
    EOS Integrated Cleaning System (seems nice to me. No problems with dust so far)
    Anti-static coatings on sensor surfaces plus anti-dust materials in the camera body
    Separate low pass filter with ultra-sonic vibration
    Software based dust mapping / removal
    Nine point Auto Focus sensor (same as EOS 30D) with F2.8 support (haven't used the XT, but I doubt this is a huge difference)
    Continuous shooting burst up to 27 JPEG and 10 RAW images (vrs 14/4. Not important to me.)
    Single large, bright, 2.5" LCD monitor with 160° viewing angles (horizontal and vertical) (I really like the combined back panel. 2.5" vrs 1.8" makes it a lot easier to eyeball your results while shooting and to check your pictures before getting them on a computer.)
    New viewfinder view includes 9 AF points as well as EOS 30D style status bar
    Picture Styles, larger range of image parameter adjustment (same as EOS 30D)
    Improved user interface (haven't used the XT, but reading the reviews on dpreview, the interface looks much nicer on the XTi)
    Image magnification available in record review
    Histogram available as brightness (Luminance) or RGB (Red, Green, Blue) (makes histogram much easier to interpret)
    Three settings for long exposure noise reduction (adds Auto option) not something I've played with honestly)
    Auto rotation with three options (not recorded, record don't rotate, record and rotate) (minimal, but nice)
    Additional custom functions (magnified view in record review, LCD display at power on)
    Up to 9999 images per folder on storage card
    Automatic storage of setting adjustments (no longer requires a press of the SET button)
    Improved print / share / direct print features
     
  4. M@lew macrumors 68000

    M@lew

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    #4
    1) The camera won't let you adjust the Aperture out of the lenses range.

    2) Dust isn't really THAT big of an issue if you're not changing your lenses every 5 sec. If you think that the XT is for you then go for it. Whilst the XTi is nice, if you prefer to save some money and get the XT, that's still a very good move. :)
     
  5. miloblithe macrumors 68020

    miloblithe

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    #5
    The estimates I've seen are 50,000.

    http://www.the-digital-picture.com/Reviews/Canon-EOS-400D-Digital-Rebel-XTi-Review.aspx

    Which is borne out by this database:

    http://www.olegkikin.com/shutterlife/canon_eos350d.htm

    43,300

    Also, you can repair a camera when the shutter malfunctions. My friend just repaired his Nikon D100 for, I think, $200 or so rather that shell out $900-1500 for a replacement camera. My hope for myself is that the camera will last me about 10 years by having one repair at about 5-6 years. I'm on a pace of about 7000 actuations this first year of owning the camera. I'm an optimist. Theoretically, it might only last until my daughter throws it off the balcony (9th floor), or something.
     
  6. JFreak macrumors 68040

    JFreak

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    Location:
    Tampere, Finland
    #6
    My recommendation would be to find a good 2nd hand Canon 10D from eBay. The thing has metal body and can take some serious abuse! It's "only" 6MP, but I do like its pictures more than the plastic Digital Rebel (or 300/350/400D in europe). For some reason, not all sensors are made equal...
     
  7. bmat macrumors 6502

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    Location:
    East Coast, USA
    #7
    The first question has been answered, so I won't bother.

    I will say the advances between the XTi from the XT are pretty significant -- most important in my mind is that they put the 20/30D autofocus system into the XTi. So while the XT was a great entry level DSLR, the better autofocus system really makes a big difference imho.
     
  8. disdat thread starter macrumors regular

    disdat

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    #8
    Thank you everyone for your awesome replies! Wow, I really received more information than I expected.

    I looked at all the posted links, and will still be doing some more research before making my final decision. But you all have given me lots to go on!

    Thanks!
    :D
     
  9. Lovesong macrumors 65816

    Lovesong

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    #9
    Ah... my bad. I thought I had read somewhere on some forum that it goes 20-ish, 50-ish, 100-ish for the Rebels, 20/30D, and 5D respectively. Thanks for correcting me.

    My point was, nonetheless, that when the camera stops functioning 5 or 10 years down the road, you will be faced with the decision of whether to repair it ($200 now, but what happens when the tech used in today's cameras is antiquated, no longer available, and thus harder to get a hold of), or get the new entry models with either the 30MP sensor, or the upgraded version that has the sensor that captures souls when a picture is taken ;)
     
  10. miloblithe macrumors 68020

    miloblithe

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    #10
    Be sure to look at this thread:

    http://forums.macrumors.com/showthread.php?t=257862

    if you already haven't. Lots of links for selecting lenses. In the long run though, just remember that any decisions you make are going to be secondary to enjoying taking lots of pictures.
     
  11. Mantat macrumors 6502a

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    Montréal (Canada)
    #11
    Get the XTi, as mentionned, the autofocus is MUCH better and that will improve your pics more than any other feature of the camera.

    Photography isnt a cheap game, you get what you pay for and most of the time, when you try to go cheap, it comes straigth back at you at the worst possible time.

    Once you have your camera body, your first purchase should be a 50mm1.8. Get it used if you can to save some cash from someone who upgraded to the 1.4 version. This is going to be your best lens for a while! On a 1.6 crop body, this is the perfect portrait lens. Then get a 2gig card, no need to buy the super exepensive one with super fast writing speed since you will probably never need it.

    After that, it all depends of what you want to shoot but the battery grip is a nice thing to have, same with circular polarized filter.
     
  12. disdat thread starter macrumors regular

    disdat

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    #12
    Thank you for the advice guys, and I am back with a new question. I didn't start a new thread because it is more of an update to my (previous) second question.

    I went to Ritz to check out the cameras. I held an XT, XTi, and a D40.

    I didn't necessarily know exactly what I was looking for, but I wanted to feel the grip, because that is what everyone seems to advise.

    My question is, how do you hold a dSLR? Is it one handed, by the grip, or is it two handed, with your other hand under the lens area? Or is it one handed when you are messing with the settings?

    I really don't think the D40 is for me, but it felt more comfortable in my hand than the XTi. I have long fingers, and my fingernail on one finger felt like it was jammed in the XTi grip.

    He quickly put away the XT, so I didn't get a chance to mess with it longer, but it felt a 'tad' better than the XTi.

    I am a little sad, because now I feel more confused, and I don't want to make a mistake.

    Oh and my current camera is a Canon G6, which I love; the grip is comfortable and I can take photos with one hand.
     
  13. miloblithe macrumors 68020

    miloblithe

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    #13
    Good point about parts. And definitely the more time that passes the less the repair will be worth. Although I do think cameras don't age anywhere near as quickly as computers. I think as long as it still works, a 4-year old DSLR will be fine in 4 years, while a 4-year old computer is old.

    Also, the reality is that how long an individual's shutter will last will depend on luck and how careful they are with their camera. Say it's 50,000 on average, if you're unlucky it'll break right after the warrenty expires. If you're really lucky it'll still be going strong at 100,000 or 150,000 and you decide to replace the camera anyway.
     
  14. miloblithe macrumors 68020

    miloblithe

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    #14
    That's so obnoxious, and not surprising for Ritz.

    I hold my camera with two hands, and really that's the best way to hold a DSLR so that you keep it steady. One hand supporting a heavy camera is going to cause shake. You can get these straps that allow easier holding with one hand:

    http://www.bhphotovideo.com/c/product/366416-REG/Sunpak_620740_Contoured_Hand_Strap_for.html

    but I think two hands is going to be easier.
     
  15. disdat thread starter macrumors regular

    disdat

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    #15
    Yeah, I just wanted to check out the cameras, and he kept asking me what kind of photos I was going to take, blah blah blah. I don't mind them asking this sort of thing, but it is obvious they really don't know much about what they are talking about. He was shocked that I wanted the body only, and he didn't think anyone sold it that way.

    Anyway, that strap thing looks interesting, but yes, it does feel more comfortable and 'controlled' with two hands.

    I am just confused where to put my hands then. While holding it with both hands, it felt okay, but I can't be sure; I don't think I was paying attention, because I wasn't sure what I was supposed to do.

    Do you hold it with two hands while you are adjusting the settings? Is it supposed to be a fluid motion when you are hitting buttons and levers?

    I did have a film 35mm way back when, and I remember how to hold it, but the XTi is different.
     
  16. bocomo macrumors 6502

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    New York
    #16
    the smaller cameras can feel a bit weird at first (adding the battery grip helps). i have the rebel xt and that was my main concern at first - it felt like a toy compare to the 10D and 20D. you get used to it and also used to where the controls are for changing the setting as you shoot (really love the thumb wheel for changing aperture - much easier than on the rebel xt)

    also, i think the larger lcd on the xti is a big improvement too

    basically, i'm just saying that a new camera, like anything else, takes some time to get used to. you seem like you've really thought it over, just get what you are comfortable with and take tons of pictures
     
  17. disdat thread starter macrumors regular

    disdat

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    #17
    This makes me feel better. I have to get a feel for it, and find my own rhythm. I think no matter what, any new camera will feel awkward initially, but I do have a way of adjusting myself to fit with objects that are initially different.

    And did you mean that the XTi has an easier thumbwheel. You typed XT, so I was not sure.

    I still haven't 100% decided on which camera yet. XT or XTi. I am making lists, and although the XTi has a lot of good qualities I am still thinking of the extra savings that I could spend on gear.
     
  18. Mantat macrumors 6502a

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    #18
    Disdat, try the XTi with the battery grip, that is a huge improvement!

    You really shouldnt thing about the XT unless you are low on cash, the XTi is a much better improvement thanks to its autofocus and bigger LCD.
     
  19. sjl macrumors 6502

    sjl

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    #19
    The right hand holds the camera on the side, with the forefinger (that finger next to the thumb :p) over the shutter release. The left hand is generally on the lens, to work either the zoom control, or the focus ring.

    When shooting with a heavy lens (eg: Canon's 70-200mm f/2.8, Canon's 100-400mm, etc.), the left hand must support the lens. Don't want to risk damaging the camera with the torque the lens puts on the mount ...
     
  20. OutThere macrumors 603

    OutThere

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    NYC
    #20
    As far as dust goes...the dust system shouldn't really be a deciding factor when buying a new camera. It's like extra cup holders or heated seats in a car. Nice, but really not key to the purchase decision.

    I'm about to break 8000 exposures and countless lens changes on my original Rebel and I have not once had dust on the sensor, and I worry about it so I check pretty often. Like I said, dust is more of a minor worry.

    Personally I'd take the XT, and put the extra money towards lenses. I'd say having a breadth of lenses is much more desirable than a moderately better camera body. Remember, your lenses will outlive the camera, so an investment in good lenses is always a good choice.
     
  21. failsafe1 macrumors 6502a

    failsafe1

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    #21
    Folks are giving you good advice. I'll add mine. You can always clean a sensor. $200 saved could mean the difference between an OK lens and a really good one. Buy the best glass you can afford. Skimp on the body some if you have to. The faster the lens the better for low light, sharpness, depth of field etc. So look for the smallest F stop number you can afford. 2.8 being the goal on most lenses. There are other example of F1, F1.4, F1.8 etc. but 2.8 for zooms and telephotos is a good goal. F4 would be the next best thing. Try to avoid lenses that list two Fstops in the description the Sigma 15-30 lists itself as a 3.5-4.5 meaning it's maximum F stop changes with the zoom range. Good luck. Starting with a new camera and learning how to shoot photos is a great adventure.
     
  22. disdat thread starter macrumors regular

    disdat

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    #22
    Hello all!

    I went to a different Ritz Camera store, and this time, the girl was more knowledgeable. I asked her a few questions, and held both the XT and the XTi; along with the D40 again.

    I like the Canons. They felt much better in my hands this second time around.

    As for XT vs XTi, I really liked the XTi's display. Much bigger and brighter than the XT especially for playback. The XT was really tiny in comparison. It is even smaller than my G6 (2 inch) - I don't know if it is a $200 option, but it has me thinking!

    I also liked the view finder in the XTi - I could adjust it to my vision and it was clearer.

    I tried adjusting the view finder for the XT, but it was blurry until the AF was active. I don't know if there was a setting to fix that.

    The self cleaning option is just a perk, as you all have assured me, it isn't a deal breaker by any means!

    As Lovesong said, the MP in the XT are just right, and that is a plus for me, but that display, along with the better AF is really tempting. It just sort of clicked with me.

    I don't need to make a decision now. I am reading some photography books from the library so hopefully I can make a purchase in a week or two.

    I really appreciate all the advice here, thank you!
     
  23. disdat thread starter macrumors regular

    disdat

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    #23
    Lenses will be another whole week of research. LOL :rolleyes: But thank you for your explanation. It helps!

    I don't know if I can afford the zoom lenses with only one f stop, but I will try to look for ones with smaller F Stops.

    Question about speed. Is speed dictated by the aperture F stop number, or is there another number? Just because a lens has a smaller F Stop, it doesn't mean it's fast, right?

    Thanks!
     
  24. miloblithe macrumors 68020

    miloblithe

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    #24
    The wider the aperture, the "faster" the lens. Take this example, there's enough light to shoot at f/2.0 and 1/60th of a second, which is probably fast enough to get a clear shot with a 40mm lens. But if your lens doesn't go down to f/2.0 but instead only goes down to f/2.8, you will have to shoot at 1/30th of a second, which means it will be harder to hold the camera steady and get a clear shot, or worse, if it's f/4.0 at the widest aperture, you'll need to 1/15th of a second to expose the picture, harder still to get a clear shot.
     
  25. M@lew macrumors 68000

    M@lew

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    #25
    Yup, as the lens is wider or the "hole" is bigger, it lets more light in meaning the lens doesn't have to be open as long, making it faster. :)
     

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