GAS pains - musings on lenses

[GLS]

In the case of the comparison between 135 and 6x7, the markedly different aspect ratio is the reason for the subjective difference. If you crop the 135 image to match the one from 6x7, it should appear identical.

I don't agree that it is simply due to differences in aspect ratio. 6x7 and 4x5 are very similar in that regard, and yet there is a clear difference in the image rendering. You can compare the output of the Fuji GSW690's 65mm lens compared with a 28mm on 135. Both have identical aspect ratio and field of view, yet the differences in image rendering between them is clear, even though it is less obvious than with wider angle cases like I previously mentioned. It isn't simply due to differences in depth of field either.

Anyway, I suspect we may just go in circles on this one, so quite happy to agree to disagree. We've probably derailed this thread long enough

 

[bernard_L]

Ok, but d consider that

But none of that is the case. Empirically it obviously isn't, and that "on the larger format you are forced to be further away to achieve the same subject framing" also isn't the case (not when measure from the optical center of the lens).

+1

GLS said: ↑
https://en.wikipedia.org/wiki/Perspective_distortion_(photography)
In a nutshell, a larger format requires a longer focal length to achieve the same angle of view. If a subject is therefore shot with the same framing on two different formats using "equivalent" focal lengths, the larger format will give rise (...)

You provide a reference to a Wikipedia article, then proceed (presumably for the convenience of forum members) to provide a summary ("in a nutshell") of said article. Except that nowhere in that article is it stated that a larger focal lengtg associated with a larger format, with identical field of view, will give rise to less (or more) perspectve distortion.

 

[BradS]

I don't agree that it is simply due to differences in aspect ratio. 6x7 and 4x5 are very similar in that regard, and yet there is a clear difference in the image rendering. You can compare the output of the Fuji GSW690's 65mm lens compared with a 28mm on 135. Both have identical aspect ratio and field of view, yet the differences in image rendering between them is clear, even though it is less obvious than with wider angle cases like I previously mentioned. It isn't simply due to differences in depth of field either.

Anyway, I suspect we may just go in circles on this one, so quite happy to agree to disagree. We've probably derailed this thread long enough

The rendering may be very different but if the object distance is the same then, by definition, the perspective is also the same.

 

[Sirius Glass]

Possibly I am using the wrong terminology to describe the effect I mean, but to my eyes there is a very obvious difference in how "equivalent" focal lengths render images on different format sizes, because of the different actual focal lengths involved. In the case of wide angles, objects will become stretched in shape towards the edges - and especially the corners - of the frame to a greater extent on the smaller format. A 24mm on 135 will show this much more than a 45mm on 6x7, which again will show it more than a 75mm on 4x5. To me wide angle shots taken on medium and large formats have a much more pleasing, true-to-life quality to them, for this very reason.

When I compare 135 with Hasselblad's lenses which shoot a 6x6, I found that the horizontal field of view is most useful. However for quick comparison I use the ratios of the normal lens, 50mm and 80mm.

SWC is 38mm:
38 * 50mm = 23.75mm
80mm

Hasselblad Fisheye:
30 * 50mm = 18.75mm
80mm

150mm lens:
150 * 50mm = 93.75mm
80mm

250mm lens:
250 * 50mm = 156.25mm
80mm

 

[GLS]

The rendering may be very different but if the object distance is the same then, by definition, the perspective is also the same.

I already conceded that perhaps I was using the term perspective distortion incorrectly here. My apologies if this is the case. Perhaps there is a more appropriate technical term to describe the effect I was referring to earlier.

 

[MattKing]

It might be the case that what you are observing has more to do with the lens types that are employed by the lens designers.
For example, a wide-angle lens for a 6x7 SLR is much more likely to be a retro-focus design than a wide angle lens for a view camera equipped with a bag bellows.
I'm wondering if you might see similar differences if you compared the rendering of the 43mm lens for the Mamiya 7 with the 45mm lens for the Pentax 67.

 

[logan2z]

While I'm tracking down a nice 50mm Distagon, I've started to think about a 150mm or 180mm for the Hasselblad. I don't generally do portraits but thought that one of these short teles might give me some extra reach for landscapes and other situations - and would be useful for portraits should I start to shoot them in the future.

I've been doing some research on the 150mm vs. the 180mm and they both seem to be highly regarded. I'm leaning towards the 180mm, despite the fact that it's a bit more expensive and some people complain about the front-heavy handling (I'd shoot it on a tripod so not sure that's an issue for me). Anyone (@Sirius Glass ?) have experience with both lenses and care to weigh in on which would be the better choice?

 

[AndyH]

I have the 150, which I bought simply because it was the proverbial deal "too good to pass up". It's become one of my favorite lenses. I have tried the 180 in a store setting, but I found it too heavy and bulky for easy use. I scarcely know when I have the 150 in place. At just about twice the "normal" focal length, I have always found a use for this length in 35mm format cameras, and I use it similarly on my Hasselblad. It's a highly individual choice, but I'd say you probably don't need both.

Andy

 

[logan2z]

I have the 150, which I bought simply because it was the proverbial deal "too good to pass up". It's become one of my favorite lenses. I have tried the 180 in a store setting, but I found it too heavy and bulky for easy use. I scarcely know when I have the 150 in place. At just about twice the "normal" focal length, I have always found a use for this length in 35mm format cameras, and I use it similarly on my Hasselblad. It's a highly individual choice, but I'd say you probably don't need both.

Andy

Thanks for the input.

I don't know what a good deal on the 150 looks like these days but one in excellent condition seems to be around $350 at the moment.

After doing some additional research I am concerned that the viewfinder vignetting of the 180 on my 500 C/M will hamper use of the lens and the 150 will be the better choice.

 

[AndyH]

Thanks for the input.

I don't know what a good deal on the 150 looks like these days but one in excellent condition seems to be around $350 at the moment.

After doing some additional research I am concerned that the viewfinder vignetting of the 180 on my 500 C/M will hamper use of the lens and the 150 will be the better choice.

Hasselblad gear has increased alarmingly over the past two or three years. I got mine for under $200, which definitely ranked as "too good to pass up", even a year ago. I didn't notice any vignetting on the 180 in the store, but I didn't take it out into bright daylight either. I love using this lens!

Andy

 

[logan2z]

Hasselblad gear has increased alarmingly over the past two or three years.

It seems to have, yes. The 180mm is now around $600 and the 50mm is close to $900, in excellent condition.

I wish I would have started building a Hasselblad system earlier.

 

[AndyH]

It seems to have, yes. The 180mm is now around $600 and the 50mm is close to $900, in excellent condition.

I wish I would have started building a Hasselblad system earlier.

OUCH!

I got my 50mm on eBay for $210 last March, and the 150mm for $175 in October (that's why I couldn't turn it down...). Both were the older silver finish models, but the shutter speeds are accurate and the glass is very clean. So they don't have the latest multi-coatings? That's what lens shades are for.

Andy

 

[Sirius Glass]

I do not take portraits so my 150mm lens is my least used lens. The 150mm lens is a good telephoto lens, but I use the 250mm lens more. I have heard that the 180mm lens is better for portraits. I have not handled or used the 180mm lens, but if I were to do portraits I might consider it. Consider which lenses together make sense. I recommend: 50mm, 80mm, 250mm or 50mm, 100mm, 250mm lenses. What it really comes down to are which lenses you would want to use.

I recommend the CF or later lenses which for the most part use the B60 filters. That way one set of filters will cover most of the lenses.

 

[logan2z]

OUCH!

I got my 50mm on eBay for $210 last March, and the 150mm for $175 in October (that's why I couldn't turn it down...). Both were the older silver finish models, but the shutter speeds are accurate and the glass is very clean. So they don't have the latest multi-coatings? That's what lens shades are for.

I should have mentioned that the prices I quoted are for CF T* lenses. I haven't looked closely at prices for the older C lenses but I assume they are lower.

 

[logan2z]

What it really comes down to are which lenses you would want to use.

Agreed. Unfortunately I don't think I'll really know until I actually try some. With the way prices seem to be going there's probably not much harm in buying a few and selling the ones I don't use. Probably the only way I'll know for sure what works for me.

 

[Sirius Glass]

Agreed. Unfortunately I don't think I'll really know until I actually try some. With the way prices seem to be going there's probably not much harm in buying a few and selling the ones I don't use. Probably the only way I'll know for sure what works for me.

Buy them from KEH, try them and if you don't like it, send it back.

 

[AndyH]

I should have mentioned that the prices I quoted are for CF T* lenses. I haven't looked closely at prices for the older C lenses but I assume they are lower.

I checked these as well. The discount is crazy high for the C series. A good value, IMHO. But whichever you buy, the prices are trending up faster than any investment, let alone any collectible.

Andy

 

[Sirius Glass]

While C lenses are less expensive, mixing C lenses and later lenses mean having two sets of filters, B50 and B60. B50 filters are getting harder to find if at all in some colors.

 

[logan2z]

I ended up coming across a nice Hasselblad 50mm/f4 CF T* so I decided to pick it up. I'm still waffling on the 150mm, since I don't do a lot of portraits. But I'll probably pick it up to complete the 50/80/150 kit at some point.

 

[Sirius Glass]

I ended up coming across a nice Hasselblad 50mm/f4 CF T* so I decided to pick it up. I'm still waffling on the 150mm, since I don't do a lot of portraits. But I'll probably pick it up to complete the 50/80/150 kit at some point.

Then you will find the 250mm much more useful. It is about 3:1 image magnification. The 250mm is one of my more used lenses and the price is not that much different.

 

[logan2z]

Then you will find the 250mm much more useful. It is about 3:1 image magnification. The 250mm is one of my more used lenses and the price is not that much different.

I may have to pick up a 501 C/M body to use the 250mm, I think the viewfinder vignetting of my 500 C/M may prove problematic with the 250mm.

 

[Sirius Glass]

I may have to pick up a 501 C/M body to use the 250mm, I think the viewfinder vignetting of my 500 C/M may prove problematic with the 250mm.

That is not really a problem. A thin line will appear at the top, it does not effect the photograph and soon you will not notice it. I do not notice either with the 500mm and 500mm with the 2XE.

 

[logan2z]

That is not really a problem. A thin line will appear at the top, it does not effect the photograph and soon you will not notice it. I do not notice either with the 500mm and 500mm with the 2XE.

This is what made me think the effect could be fairly dramatic on lenses longer than 150mm:

http://www.dmin-dmax.fr/photoe2f.htm

These images are from a 503CX so I don't know if the effect is worse/better/the same with a 500 C/M. I also understand the effect can be somewhat dependent on which focusing screen is used.

 

[Sirius Glass]

This is what made me think the effect could be fairly dramatic on lenses longer than 150mm:

http://www.dmin-dmax.fr/photoe2f.htm

These images are from a 503CX so I don't know if the effect is worse/better/the same with a 500 C/M. I also understand the effect can be somewhat dependent on which focusing screen is used.

I have he 503CX and the line is very thin. The author of that has a problem with his own camera. There should be no problem with a camera that is properly square up [requires a Hasselblad repair person and a jig] and a properly mounded viewing screen.

 

[logan2z]

I have he 503CX and the line is very thin. The author of that has a problem with his own camera. There should be no problem with a camera that is properly square up [requires a Hasselblad repair person and a jig] and a properly mounded viewing screen.

I thought those images looked pretty extreme. Thanks for the info.