[BigDave]

N:

You may also want to see if you can pick up a shift lens. This will help you control perspective problems. Anyone have experience with the Arsat 80mm?

[RioRico]

Any ultrawide lens distorts, whether rectilinear or any of the various fisheye projections. Such distortion is unavoidable, same as map projections; it's like pounding a round peg into a square hole, or squaring the circle, or whatever. This isn't just a UWA problem either. Pan with a 24mm lens and you can watch the frame edges transform.

So you need to decide on your comfort level for distortion. And that depends on what you mean by 'architectural' photography. Interiors or exteriors, 'normal' viewpoints or panoramic spreads, reality or interpretation, etc. If "straight reality" is your goal, know that anything wider than 28mm distorts on an APS-C frame. So put an M28 onto a pano-head tripod and stitch-together a true representation. Fisheyes work inside round structures and at corners, or can be carefully oriented so as to distract from their distortion, or can be defished.

So the other cure for unavoidable distortion is PP. And that depends on how you'll display your architectural photos. Defishing, and perspective and barrel/pincushion correction, and other geometrical transformations, can push pixels further apart, ie, you lose resolution. Heavily-transformed images won't be suitable for large prints subject to close inspection. With smaller prints, or prints kept a safe distance from prying eyes, that won't matter. If detail *does* really matter, use a 4x5" viewcam and a 50mm Zeiss.

And don't forget the tripod.

[taiweitai]

The Samyang 14mm would be your best bet for your budget. You are able to get a Sigma 10-20 first gen used for that price if you are lucky. Tamron 10-24 would be a choice too, but i would put this last on my list. comparing with the other two mentioned.

I am using Sigma 8-16 and really happy with the lens. The only thing about it, its really the price tag.

[Andi Lo]

N:

You may also want to see if you can pick up a shift lens. This will help you control perspective problems. Anyone have experience with the Arsat 80mm?

The arsat lenses, even the 35mm, is way too narrow for "normal" architecture shots on a crop sensor. If you use a film camera it should be useable though.

[nron]

Thanks for all the replies guys! I have been looking at the Sigma 10-20's and was wondering, is it really worth the extra $200 to get the f/3.5 model over the f/4? I hadn't even heard of the Sigma 8-16, but at ~$700 new I just don't think I can justify that much more of an investment for 2mm more at f/4.5. Am I wrong in this assumption? Is that lens really worth the extra scratch?

Also, as far as the TC's go, I know it's both a bit off topic and they aren't a great solution, but what I'm really looking at is extending the versatility of my kit the greatest amount possible without spending a fortune that I don't have. I'm trying to transition from a completely amateur photog to a freelance professional, and am really trying to cover all my bases. If a 1.4x or 1.7x would be a lot more usable than a 2x (which from your comments it seems like) then I am all about going that route instead. What I'm hearing is that 1.4x would put me at ~420mm equiv. on my 55-300 and a 1.7x would be like having a ~510mm. Am I right with these assumptions? Is it worth it? If so, 1.4x or 1.7x, which would be best, and what brand/model is decent?

Along these same lines of being a bit off topic and extending my kit's capability on the cheap (I should've titled the thread: getting the best versatility bang for my buck). Has anyone used a 49mm filter thread macro reverse rings (mouthfull)? I have an FA 50mm f/1.4 and supposedly I could add another macro to my kit for ~$10 by getting one. Is this the only lens that works with the ring, and is it a total gimmick, or actually usable? Sorry again, for cramming so many questions into this thread, but I've gotten a lot of great anecdotal info already, thought I'd ask.

[Andi Lo]

Thanks for all the replies guys! I have been looking at the Sigma 10-20's and was wondering, is it really worth the extra $200 to get the f/3.5 model over the f/4? I hadn't even heard of the Sigma 8-16, but at ~$700 new I just don't think I can justify that much more of an investment for 2mm more at f/4.5. Am I wrong in this assumption? Is that lens really worth the extra scratch?

Also, as far as the TC's go, I know it's both a bit off topic and they aren't a great solution, but what I'm really looking at is extending the versatility of my kit the greatest amount possible without spending a fortune that I don't have. I'm trying to transition from a completely amateur photog to a freelance professional, and am really trying to cover all my bases. If a 1.4x or 1.7x would be a lot more usable than a 2x (which from your comments it seems like) then I am all about going that route instead. What I'm hearing is that 1.4x would put me at ~420mm equiv. on my 55-300 and a 1.7x would be like having a ~510mm. Am I right with these assumptions? Is it worth it? If so, 1.4x or 1.7x, which would be best, and what brand/model is decent?

Along these same lines of being a bit off topic and extending my kit's capability on the cheap (I should've titled the thread: getting the best versatility bang for my buck). Has anyone used a 49mm filter thread macro reverse rings (mouthfull)? I have an FA 50mm f/1.4 and supposedly I could add another macro to my kit for ~$10 by getting one. Is this the only lens that works with the ring, and is it a total gimmick, or actually usable? Sorry again, for cramming so many questions into this thread, but I've gotten a lot of great anecdotal info already, thought I'd ask.

f3.5 is worth it for the HSM and the slightly faster aperture; if you don't need these two features, the old version is better bang for buck

As for the TC, what are you planning to shoot professionally with it? for sports or BIF I know for sure that it just won't do. You're not really expanding your equipment's capability there.

[taiweitai]

if you are looking at the price tag of the new Sigma 10-20 and the 8-16, it is about the same.
the reason i got the 8-16 not the 10-20 is that i got 16-20mm covered already and i love the result that i saw with the 8mm. Its a safer for you to get the 10-20 since you cant really mount a filter on the 8-16.

It was hard for me too couple months ago to make this call. I know there are fans out there for the newer 10-20 but i would go the older one since 1/ Seems like Photozone prefers the result of the older version after testing the new one 2/ the aperture would not make a big impact on UWA at all. DOF is pretty much set infinity if object is set 3ft or further away. 3/ HSM is a good thing but also would be a nightmare if there is any QC problem. 4/ get a used old version of the Sigma 10-20. if you dun like it, sell it at the price you got, no big deal. 5/ You might want to use some filter. The filter size for the new 10-20 is 82mm vs 77mm on the old one, you will save a lot of green not only on the lens price tag but also save some on the filter budget.

[Lowell Goudge]

Just one additional point about the new 10-20 over the old

I believe the F3.5 is constant over the entire range. The old is F4-5.6

While it is only a half stop at the wide end it is 1 1/2 stops at 20 mm

[taiweitai]

Just one additional point about the new 10-20 over the old

I believe the F3.5 is constant over the entire range. The old is F4-5.6

While it is only a half stop at the wide end it is 1 1/2 stops at 20 mm

constant aperture is surely a good thing, so u almost dun hv to change any setting at all as u zoom in n out. but on uva lens the effect on f-stop would be minimal.

When u looking at f stop u hv to related that to the focal length too. The light gathering capacity is different on a 100mm 2.8 and a 28mm 2.8 lens. Its all depends on the aperture area and u hv to throw the focal length as a factor in that equation. Lets see the aperture area difference on a 20mm lens between f/5.6 and f/3.5; the area of aperture on f/3.5 is about 15 mm sq. more than f/5.6

mmmmmmmmmm , sounds like a lot

but when u look at the area difference between a 100mm lens on f/5.6 and f/3.5 is 390mm sq.
difference of a 300mm lens is 3500mm sq.
a 500mm lens has a difference of 9700mm sq. !

so what it means is the f stop difference on a shorter lens would have less effect than when you r comparing the longer lens.

since for uva is the widest lens u can get, the f-stop factor is not as big as when u look at the other lens.After all these calculation, i walked out of this miserable situation for deciding what uva lens to buy and ended up with the" slower but doesn't reli matter" Sigma 8-16.

but yeah, i have been trapped in there before, not until the painful process of going to the library to read books about the physics.

* but still, my opinion is still objective and i know that well lol :P