Full Frame Pentax!!!!!!!

Surely one big advantage of full frame is the shallow depth of field possible with large apertures. APS-c does have a wider DofF for the same aperture setting.

Yes, that's been mentioned already.

I hate to be the one to urinate on the meat grilling aparatus, but acording to my calculations a FF sensor with the same pixel pitch as the K7 would have to be ~32MP.

Area goes like the linear dimension squared.

On the plus side, lower pixel pitch means better noise characteristics, but you are going to need to project a larger image if you want to get the same result as we currently enjoy on APS-C. Larger image = longer focal length.

I'm much too lazy (not to mention poor) to lug a 450mm F2.8 lens around with me, so I'll stick with my APS-C DSLR thanks.

32MP is a wee bit high, the 12MP FF seems to work fine, even as JPEG.
link

You can view in full size, I think?

The focused target size would be no different whether FF or APS-C. A 300mm lens is 300mm regardless of what is behind it.

Do you only refer to FOV in respect of 450 on a FF?

Regards

You have to crop a FF image to make it the same as an APS-C image unless you use a longer lens.

What is the advantage of FF if you're going to crop it?

FOV is highly relevant to lens choice. If you have a larger format, you need longer lenses to take advantage of it.

I agree with you about the crop, I dont always crop my FF images or APS C images.

By your question of whats the point, indeed, why bother with anything larger than APS-C?

What is so special about APS C and why is it your only acceptable format? You are only comparing FOV here.

Would you advocate cropping medium format images to APS C? If not, why not?

Regards

If you agree about the crop then you agree about longer lenses. You even said earlier than you use longer lenses yourself rather than cropping.

I would bother with something larger than APS-C if it was practical and affordable enough for me. Once I had it, I would want to use appropriate lenses with it to get the full advantage from it. That means using a 450mm lens instead of a 300mm, for example.

That's my only point. I'm not anti FF.

ps. I used to use FF myself as well. It was called 35mm film

I have legacy Pentax lenses from my film days that would work perfectly well on a full frame camera body, but I also have a range of APS-c lenses that would not.

Most of my expensive lenses are in the latter category, so a full frame camera would involve me in considerable expense beyond just the body.

I would need to think long and hard about that before I were tempted to change. Probably so would a lot of other people in the same boat.

I am not sure that Pentax would sell enough to make it worthwhile unless it were a pro beater, but lots of Pros are going for mirrorless cameras of the micro 4/3rds variety so I understand. it is a big decision for a smaller company to make.

Pete,

Yes I agree that to get the same FOV from a 300 on a FF as the same lens/conditions as an APS C you wouls crop the larger FOV down.

My point is that I don't shoot FOV. If I do a golf comp, my positioning is generally fixed at most holes etc. I use a tele lens. Whatever FOV I get is what the shot is taken at. I then crop to suit the shot/image content.

The distance is the main issue here, not FOV. As I said before, the magnification is the main issue for me. A 300mm on my K7 provides exactly the same target object size as a 300mm on my D700. The D700 has less DOF and a larger FOV. So isolation, cropability or increased surround image are options I have.

I think better disussed over a pint, with both systems and lenses present.

Regards

Surely if you've got a 300mm on each, the DoF is the same. Granted, if you were to use a 200mm on the K-7 to get the same FoV, then the DoF would be greater.

Dan

K10D, Do you agree that you generally get better image quality when using a longer lens than when cropping? If so, FOV is highly important.

You don't want excessive FOV if you could have done better by having a smaller FOV.

All I'm claiming here at the moment is that you need longer lenses on a larger format to get the full advantage of that format - and I'm sure I'm right on that as it's so simple.

The grey area is about whether you can get just as good results with cropped FF as uncropped APS-C with the same lens. I don't understand the maths well enough to argue about that, so I'm leaving it to others.

Can't go into the science but a lot of point & shoot apertures never go lower than f8 as there DOF is equal or greater than a DSLR at f16.

an interseting site.link

Regards

Hmmmm.

What about if I set my D700 to APS C and shoot with a 200mm lens, then I take the same shot on FF. Assuming the "sunflower" didn't move, what would be the difference when both shots are printed to an A4 print?

The cropped shot would have a larger "sunflower" as the printing has a factor of 1.5 where as the FF shot would be with a larger FOV of course.

Now I agree that to get the FF shot to match the cropped shot I would need a 300mm lens to get the same FOV, but the "sunflower" is also larger as the magnification of the lenses is different. Effectively 4x closer for the 200mm but 6x closer for the 300mm lens.

Hence I dont sort of consider FOV when composing, yes I need "in frame" images of what I want but generally use longer glass than wider.

Your right about FOV and longer glass but it is not relevant if we can afford or not, nature shooters still require longer glass, more for the magnification than FOV.

Regards

Quoted from that link:
So if you use the same lens, and stay in the same place, the DoF will be the same. Imagine your FF sensor. You take a shot, then crop that image down to APS size. Why would the DoF change?

The DoF with a compact camera is more because the focal length can be a lot shorter to get the same FoV as a DSLR.

Dan

Quoted from that link:
So if you use the same lens, and stay in the same place, the DoF will be the same. Imagine your FF sensor. You take a shot, then crop that image down to APS size. Why would the DoF change?

The DoF with a compact camera is more because the focal length can be a lot shorter to get the same FoV as a DSLR.

Dan[/quote]Sorry Dan, your correct. With the same lens /subject distance as above.

I was probably remembering something about the group f/64 club where they had to use f/64 to get acceptable DOF on large plate cameras.

Regards