165 f/2.8 OR 200 f/4 for Pentax 6x7?
Posted 09 May 2013 - 01:31 AM
The one I'm looking at is being sold with a 105 f/2.4 lens, for $460, including shipping from Japan. It's from a professional camera seller who has replaced the light seals. I asked him a question about the lens condition, and if he answers the way I hope he does (and if someone else doesn't buy it first), I'll buy it.
I'm also planning to get either the 165mm f/2.8 or the latest 200mm f/4. Having both would be nice, but isn't possible. They seem to both be great lenses, from everything I read, but I'd be grateful for opinions. Is the 165 so close in focal length to the 105 that the 200 makes more sense? Is the 2.8 aperture on the 165 brighter than the 200's f/4, making focusing easier? Is one optically better than the other?
I'd like to get the latest version 55mm f/4, because I hope to use this for daytime photography, too, but that will have to wait a bit (the check wasn't that big).
Posted 09 May 2013 - 09:26 AM
Posted 09 May 2013 - 05:58 PM
I have used the system for over 6 years after deciding to go medium format over digital. A wise choice then and perhaps so even today.
As far as lenses go, the 165, 200, and even the newest 55 you mention are all excellent.
The 165 has the advantage of the f/2.8 stop and offers a flat field at f/4.8 (so does the 105 as well) Stars are sharp to the corners with a wide open aperture. The portrait perspective is an ideal one for intimate areas of the Milky Way. I would go for this lens vs the 105 or 200.
That being said, the latest 200 is very sharp (only the 400 ED-IF is sharper in the telephoto range) but the f/4 is somewhat slow and needs f/5.6 for a flat field. With patience, this lens shot at f/5.6 offers superior images. It will depend on how long you want to expose. Hence my recommendation for the 165.
With E200 I expose my 165 @ f/4.8 for 45-60 minutes, the 200 @ f/5.6 for 60 + minutes for deep exposures under dark skies. When using the 165 @ f/2.8 20-30 minutes will do the job, and light falloff (vignetting) is not too bad. If you're a software buff you can restore a flat field to the image or crop after exposure.
I paid less than $150 for each of the 165 and 200, so look for the deals. You might get lucky and afford both!
Good film work does require good skies, so I would also look at your conditions you will shoot under.
Good luck in your acquisition of the 67.
Posted 09 May 2013 - 11:38 PM
The skies here are pretty dark away from my little town, though there are some light domes down near the horizon.
Posted 10 May 2013 - 12:40 AM
Pentax does make two excellent zoom lenses. One goes from 55 to 100 at f/4. #2 goes 90 to 180 @ f/5.6. You could probably get by with the 90 - 180 and cover a lot of landscape with just one lens. However, you would be in the slower ranges for astro. This lens is quite sharp wide open and is very versatile. But they are still on the expensive side used. Just a suggestion.
Personally, I would start with the SMC 165 and go from there. I love lenses.
Posted 10 May 2013 - 10:44 AM
The 165 is ok but is not known as one of the sharper Pentax lenses, not in the same league as the 200.
Posted 10 May 2013 - 11:17 AM
That's what I've read, too, and I may end up trying both. But what Jim and igor say makes sense. The extra stop is important for astro work. And I've seen some amazing shots taken with the 165; it's those images that have me hunting for a 6x7 right now.
Posted 10 May 2013 - 11:57 AM
The 165 has been the lens of choice since the 1980's for portrait perspective wide-field astrophotography and coupled with proper film and dark skies can still floor digital SLR's today. True story.
The newest 200 is nothing short of spectacular when used properly. It is stunningly sharp. I have to double the normal guiding magnification to ensure pinprick stars. I know of one Canon user that adapted it for his 5D and mentioned it exceeded his expensive L glass in every respect. Except convenience I would imagine.
Posted 10 May 2013 - 12:24 PM
Another lens that I prefer to 165 is the macro 135, that one is also better than the 165.
But the newer 5 element 200 is the best of all if you expect above average sharpness.
Posted 10 May 2013 - 12:46 PM
Here's where I'm getting the funds for any other near-term 6x7 stuff. I do want to get the latest 55mm, if only for landscape work. The cheapest I've seen it is $300.
Any suggestions for my next astro lens? Should I get a 165 to compare, or go for an earlier 300 (I cannot afford the latest)? Or something else, since I have the 200. The 150 is fast, and inexpensive. I'm hearing the 105 is not the best for astro, but it is very fast. (It's also not cheap, when bought on its own).
Posted 10 May 2013 - 03:41 PM
As for 300mm the early garden variety version is a so-so performer, it goes for around $300 give and take, the ED version is night & day in difference, spectacular performance and about 3-4 times the price of standard version, the comparison between these two is like achromat vs apochromat, really no contest.
Posted 10 May 2013 - 04:34 PM
Posted 10 May 2013 - 06:39 PM
I think I just found another Kodak Aero Ektar. I already have a 4x5 Speed Graphic sitting here waiting for refurbishing. I put them together and make a fairly good return. This will provide funds for the 55 and a lot more. Would a 400 or 300 ED be the next choice, if I had the funds?
Posted 10 May 2013 - 07:47 PM
Posted 10 May 2013 - 10:38 PM
I have a G-11, and hope to have it eventually mounted on a pier in an observatory.
Since we're talking astrographs, let me go a little further off-topic and ask for any recommendations for dedicated astro lenses that might be less expensive than the 400 ED-IF. There's one on eBay right now, but the asking price is $8000! I like the idea of a focal length around 400mm for a 6x7 frame.
Posted 11 May 2013 - 06:09 AM
With a G-11 you are all set for heavy mounting. I use a fork mounted SCT and this works best for me as there is no meridian flip. Most of my work involves working at the meridian.
The 300 ED IF is a stellar performer and with adapters can work with digital SLR's or CCD just fine. It's that good.
I use old Pentax glass from the early 70's on my digital and am always amazed on how well Pentax (Asahi Optical / Takumar) made their lenses. It was the era of competing with Leica and Zeiss. Yes, they were that good.
Posted 11 May 2013 - 09:14 AM
Posted 11 May 2013 - 09:37 AM
Posted 11 May 2013 - 09:41 AM
I would try to buy a Pentax astrograph. Most likely less money on the used market than the 400 ED. The 4" APO would be less useful if you wanted to use outside of astrophotography due to no iris among other features.
It's a shame to waste those nice medium format astrographs on small digital sensors. The field of view is incredible.
Posted 11 May 2013 - 01:39 PM
Posted 11 May 2013 - 02:26 PM
You can do the math for the 165 and 200 and beyond. Aperture and focal length provide greater resolution for a given field of view.
If one could manufacture a large format camera with long fast lenses, keeping the film flat and eliminating flexure, this would be a killer ap.
For medium to small object through telescopes, digital wins.
Posted 11 May 2013 - 02:47 PM
They tried that on Mount Polomar: to keep the film flat, they used huge glass plates, and they had a pretty long, fast lens, too!
I did just buy another Aero Ektar lens, so knowing I'll have more funds coming, I spent some of what I already had on a late 55mm f/4 lens. We get so few great nights for imaging here that I want something nice to use for daytime landscape shots, so I can use up a roll of film quicker.
i'd better not get too free with the cash, though: I have a 14-inch mirror on the way, and I need to build a scope around it.
Posted 11 May 2013 - 03:55 PM
The 45/4 is almost as sharp and offers the widest rectilinear image in the 67 system. I find I use this one the most nowadays. Depth of field is wonderful when doing moonlit landscapes.
Posted 11 May 2013 - 07:11 PM