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03-31-2011, 05:49 PM   #16
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Usually I favour Pentax lenses, but having my eyes openned to how handy <f2.8 is, I'd say if you have a budget of $450 then try a Sigma 30/1.4.

03-31-2011, 07:07 PM   #17
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QuoteOriginally posted by twitch Quote
Usually I favour Pentax lenses, but having my eyes openned to how handy <f2.8 is, I'd say if you have a budget of $450 then try a Sigma 30/1.4.
Considering your budget, I too would recommend the Sigma. I sold mine and wish I hadn't.
03-31-2011, 07:14 PM   #18
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I've never personally used the Sigma 30/1.4 on Pentax, but my friend is very happy with his Canon mount Sigma 30/1.4 and from all accounts it's an excellent lens. If it fits in your budget, it's probably worth taking a close look at.
03-31-2011, 09:49 PM   #19
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I had not even considered the sigma, I'm going to see if I can check one out. I went through about 2000 photos I have taken with the 50mm to check out the exif data to see how I was shooting. The majority of my keepers were all shot at f2.8 I am not camera savy but the reason seems to be that anything much lower than 2.8 and the DOF is quite narrow, narrow enough that I can only get a portion of someones face in focus. So the shots I have taken that are lower than 2.8 are for very special or unique circumstances and not with kids as I could not get their whole face in focus.

I think this is normal but does the DOF change with focal length as well as f-stop. So would shooting at F 2.0 have the same depth of focus shooting with a 50mm or 35mm or 28mm or 21mm? With my limited lenses and knowledge it seems like the answer is yes.

I guess what i am getting at is that if the lowest f-stop I am shooting with moving objects is 2.8 maybe I am better off with my fast lens being a manual and my AF lens is more of an all rounder. Sorry to blabber but I don't have many camera friends and I feel I need to talk this out with someone before pulling the trigger. Thanks in advance for any help and time put into contemplating this.

04-01-2011, 07:01 AM - 1 Like   #20
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QuoteOriginally posted by 1r0nh31d3 Quote
I had not even considered the sigma, I'm going to see if I can check one out. I went through about 2000 photos I have taken with the 50mm to check out the exif data to see how I was shooting. The majority of my keepers were all shot at f2.8 I am not camera savy but the reason seems to be that anything much lower than 2.8 and the DOF is quite narrow, narrow enough that I can only get a portion of someones face in focus. So the shots I have taken that are lower than 2.8 are for very special or unique circumstances and not with kids as I could not get their whole face in focus.

I think this is normal but does the DOF change with focal length as well as f-stop. So would shooting at F 2.0 have the same depth of focus shooting with a 50mm or 35mm or 28mm or 21mm? With my limited lenses and knowledge it seems like the answer is yes.

I guess what i am getting at is that if the lowest f-stop I am shooting with moving objects is 2.8 maybe I am better off with my fast lens being a manual and my AF lens is more of an all rounder. Sorry to blabber but I don't have many camera friends and I feel I need to talk this out with someone before pulling the trigger. Thanks in advance for any help and time put into contemplating this.
As I understand it, DOF is a combination of focal length, focus distance, and aperture. The longer the lens focal length, the less DOF. The shorter the focus distance, the less DOF. The larger the aperture (smaller the f/#), the less DOF.

Thus a 30/1.4 would have a larger DOF at 1.4 than my 58/1.4 at 1.4 if taken from the exact same distance to subject. Where you have to be careful is that with the 30, since your FOV is wider, you would likely move closer to the subject to fill the frame. I may be off here, but I think if you fill the frame with your subject with both lenses (by moving closer with the 30), the DOF will be the same.

Can I get an affirmation on this from another member? I'd hate to steer this guy wrong.

As for AF vs manual, it's really just about what you're comfortable with. My personal preference is manual focus fast primes and AF slow zooms, and it works for chasing my kids around, but what may work for me may aggrevate you.

Don't worry about blabbering, most of us are in the same boat as you.
04-01-2011, 08:03 AM   #21
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QuoteOriginally posted by jeffshaddix Quote
Thus a 30/1.4 would have a larger DOF at 1.4 than my 58/1.4 at 1.4 if taken from the exact same distance to subject. Where you have to be careful is that with the 30, since your FOV is wider, you would likely move closer to the subject to fill the frame. I may be off here, but I think if you fill the frame with your subject with both lenses (by moving closer with the 30), the DOF will be the same.
Thank you for this info, it definitely expanded my knowledge on my lenses and will change the way I currently use them, also gives some insight into what might be the most practical lens purchase at this point. I'd love to hear from anyone who can confirm this as it may help me make a decision. I'll do some hunting on the web and forum as well to see if I can find a confirmation on this.
04-01-2011, 08:35 AM   #22
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If you shoot your 50mm at 2.8, then you should not have much to complain about with the DA L 35mm 2.4 or FA 35mm 2.0. But the DA 35mm 2.8 macro will not allow you to get as thin a DOF as you would have with the 50mm at 2.8.
04-01-2011, 09:05 AM   #23
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QuoteOriginally posted by Marc Sabatella Quote
The obvious choice to me is the DAL35/2.4, even though it might possibly seem like a lens you might replace. I wouldn't rule out the DA40, though - it's a great lens, and while sure, sometimes you might wish it were faster than f/2.8, with modern cameras and their high ISO performance, it's really not that big a deal. Larger aperture just means shallower DOF, anyhow, which is usually not your friend in casual candid photography (very hard to get more than one person in focus).
+1 Both are nice and will not break the bank.

04-03-2011, 10:30 AM   #24
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ditto on the 40mm. when it comes to shooting kids fast focus is crucial and focus with the 40mm is fast! this is coming from a guy who sold his 40mm to buy the sigma 30mm

as for buying the one lens you will keep forever, i think that's not a worthwhile goal because as you shoot more you find new things you like and don't like so your your preferences change. my advice is to embrace change.

that said, if you buy quality glass you will have no problems selling it and getting a good chunk of your investment back.

good luck!
04-03-2011, 11:34 AM - 1 Like   #25
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To play with dof, check Online Depth of Field Calculator. Select camera; fill in the numbers and it gives you the DOF range.

Like Marc, I would suggest the DA(L)35/2.4. Save the rest of the money for next years budget and add a (longish) macro like Sigma 70 or105, Tamron 90 or DFA100(WR)

Gives 2 nice primes that can cover a lot of photographic circumstances.
04-03-2011, 12:36 PM   #26
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QuoteOriginally posted by sterretje Quote
To play with dof, check Online Depth of Field Calculator. Select camera; fill in the numbers and it gives you the DOF range.

Like Marc, I would suggest the DA(L)35/2.4. Save the rest of the money for next years budget and add a (longish) macro like Sigma 70 or105, Tamron 90 or DFA100(WR)

Gives 2 nice primes that can cover a lot of photographic circumstances.
Thank you. The chart is helpful and fun to play with. I'm still wavering a bit. over this. I have a few ebay sales going the next couple of weeks and if they go well I can bump my budget a bit. I might decide to go FA 43 ltd and keep the kiron 28mm f2 as well as my kit lens 18-55 and my tak 70-200 zoom/macro. Use that for a year and then re-evaluate next spring. The one catch is there is no where in Edmonton I can try a fa 43 ltd....
05-31-2011, 06:14 AM   #27
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Just a quick update. Thank you for all the responses. The advice and support of the forum has been greatly appreciated.

I ended up with the 43mm ltd. I went over my budget my 100 bucks but got a made in Japan copy and have been really happy with it. Right now I feel my kit covers a pretty solid range. I have even been using the tak 70-200mm which now that I can shoot outside is actually pretty useful and not bad quality at around f 8-16. I think I might get a lens hood for it to see if it improves quality.
05-31-2011, 07:11 AM   #28
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QuoteOriginally posted by 1r0nh31d3 Quote
I went through about 2000 photos I have taken with the 50mm to check out the exif data to see how I was shooting. The majority of my keepers were all shot at f2.8 I am not camera savy but the reason seems to be that anything much lower than 2.8 and the DOF is quite narrow, narrow enough that I can only get a portion of someones face in focus.
IMO, the main reason to go with a prime these days is not image quality. It's for some special characteristic only available in a prime, such as very compact size, very wide aperture, or macro ability. If you think you'll rarely go below f/2.8, you may be better off getting an f/2.8 zoom lens, and keeping your existing primes for the few times you want to go below f/2.8.

I've shot thousands of pictures with my two favorites zooms, the Tamron 28-75mm f/2.8 and the Sigma 50-150mm f/2.8, and I'd put them up against almost any prime under $1000 in terms of sharpness and image quality. And the Tamron would be well within your stated budget of $450.

I will probably be buying a prime soon to go below f/2.8, and I am trying to decide between the Sigma 30mm f/1.4 and 50mm f/1.4. I've been extremely impressed with the build quality of my Sigma 50-150mm, as well as the quiet speed and accuracy of the HSM. I tend to shoot mostly portraits, so I'm leaning toward the 50mm since I won't have to get as close to my subject, and it will be easier to separate my subject from the background. But the 30mm would potentially be more useful indoors with its wider field of view. So I'm still trying to decide.
05-31-2011, 08:49 AM   #29
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I agree partly with what your saying but I come at from another angle. Even though the majority of my keepers are around 2.8 there are times I need the speed but more importantly control over DOF. Most zooms don't isolate the subject to the degree that I am after. And I figure if I am shooting above 2.8 then my kit 18-55 is a solid performer. In fact I get great results with it outdoors when I can have my aperture set between 8-16, and it has the added benefit of being virtually free. Maybe I have not handled or seen the right pictures posted from users or flickr galleries but I have not experienced too many zooms that match a good primes image quality. And I think the added benefit of size and weight is a bonus.

So I guess that is where I disagree, for me the benefits to shooting with a good prime is that it is easier to get a higher quality image than with a zoom (maybe that's just my own style) and the size and weight is a secondary bonus.

QuoteOriginally posted by Edgar_in_Indy Quote
IMO, the main reason to go with a prime these days is not image quality. It's for some special characteristic only available in a prime, such as very compact size, very wide aperture, or macro ability. If you think you'll rarely go below f/2.8, you may be better off getting an f/2.8 zoom lens, and keeping your existing primes for the few times you want to go below f/2.8.

I've shot thousands of pictures with my two favorites zooms, the Tamron 28-75mm f/2.8 and the Sigma 50-150mm f/2.8, and I'd put them up against almost any prime under $1000 in terms of sharpness and image quality. And the Tamron would be well within your stated budget of $450.

I will probably be buying a prime soon to go below f/2.8, and I am trying to decide between the Sigma 30mm f/1.4 and 50mm f/1.4. I've been extremely impressed with the build quality of my Sigma 50-150mm, as well as the quiet speed and accuracy of the HSM. I tend to shoot mostly portraits, so I'm leaning toward the 50mm since I won't have to get as close to my subject, and it will be easier to separate my subject from the background. But the 30mm would potentially be more useful indoors with its wider field of view. So I'm still trying to decide.
05-31-2011, 09:40 AM   #30
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QuoteOriginally posted by 1r0nh31d3 Quote
And I figure if I am shooting above 2.8 then my kit 18-55 is a solid performer. In fact I get great results with it outdoors when I can have my aperture set between 8-16, and it has the added benefit of being virtually free. Maybe I have not handled or seen the right pictures posted from users or flickr galleries but I have not experienced too many zooms that match a good primes image quality.
Did you come across my recent thread where I posted a bunch of samples from my Tamron 28-75mm?

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/145599-tamron-...lots-pics.html

I also posted links to a couple full-size 12MP pictures, one at f/2.8 and one at f/8.0, so you can pixel-peep the actual lens quality. I would not have been able to get most of those pictures with the 18-55mm kit lens.
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