[t.manning]

From a practical point of view a 500mm is going to be hard to use handheld.

If you want to use it as a general tele lens then you might be better off getting one of the less common 300/350mm ones (Ohnar, Super Paragon, Tamron etc.).

Manual focusing is not going to be easy (catch-in-focus often does not work and depth of field is quite shallow) and unless you swap your focusing screen for a better one than the stock Pentax you might have to rely on LiveView focusing. A good deep hood is just about essential and even so you might have to tweak the contrast a bit in post-processing. Check out the Mirror Lens Club thread for many useful hints and pics.

And there are those hated or loved out of focus doughnut highlights...




... which can be avoided if you are careful.




Hours of fun and frustration await you !

Thanks for your advice kh1234567890. I recently purchased a Tamron AF 70-300 1:4-5.6 LD lens to use as my general tele lens. I would mainly be using the 500mm for shots of the moon, some macro shots, and maybe some wildlife photography if I can figure out how to avoid the out "of focus doughnut highlights".

[t.manning]

Besides the other post of advice, the moon's motion is a big factor at 500mm. You need a reasonably fast shutter speed to avoid motion blur.

Thanks for your advice Just1MoreDave. I hadn't considered the moons motion. What shutter speed do you recommend for that type of shooting with a mirror lens?

[Just1MoreDave]

Thanks for your advice Just1MoreDave. I hadn't considered the moons motion. What shutter speed do you recommend for that type of shooting with a mirror lens?

I think there are actual formulas using the field of view. Looking at my 500mm shots, I can't see obvious motion blur at 1/45 but something is not quite sharp. I would try 1/125 first.

[johnha]

The biggest problem with 500mm is going to be your tripod (holding the camera steady). On an APS-C DSLR, you're looking at approx. 15x magnification, even the slightest vibration of the camera/lens will be magnified 15 times. If your tripod/head can't hold the camera and lens securely, you may find it tips one way or the other (depending on balance). It is probably better to bump up the ISO rather than struggle with too slow speeds (at least at the beginning).

[reeftool]

I have one of those cheap 500mm f/8 mirrors. It's difficult to hold steady. I bought mine for under $50 and for the purpose of photographing my daughters college rowing team at a couple of locations where the races were 1/2 mile out on the water. It did the job although crops from my 70-300 were just as good. Surprisingly, it functions very well as a candid portrait lens from 30 feet away far better than subjects at infinity. Still, I rarely use it anymore and it needs to be on a monopod or tripod for me to use it at all. There is an f/6.3 version of these lenses that costs a bit more but is much better. Getting good shots from ANY 500mm lens takes patience and practice.

[t.manning]

I think there are actual formulas using the field of view. Looking at my 500mm shots, I can't see obvious motion blur at 1/45 but something is not quite sharp. I would try 1/125 first.

I will try 1/125 first. Thanks Just1MoreDave for all your help.

[t.manning]

The biggest problem with 500mm is going to be your tripod (holding the camera steady). On an APS-C DSLR, you're looking at approx. 15x magnification, even the slightest vibration of the camera/lens will be magnified 15 times. If your tripod/head can't hold the camera and lens securely, you may find it tips one way or the other (depending on balance). It is probably better to bump up the ISO rather than struggle with too slow speeds (at least at the beginning).

That is very helpful information. Thanks johnha.

[t.manning]

I have one of those cheap 500mm f/8 mirrors. It's difficult to hold steady. I bought mine for under $50 and for the purpose of photographing my daughters college rowing team at a couple of locations where the races were 1/2 mile out on the water. It did the job although crops from my 70-300 were just as good. Surprisingly, it functions very well as a candid portrait lens from 30 feet away far better than subjects at infinity. Still, I rarely use it anymore and it needs to be on a monopod or tripod for me to use it at all. There is an f/6.3 version of these lenses that costs a bit more but is much better. Getting good shots from ANY 500mm lens takes patience and practice.

Thanks for your advice reeftool. I will definitely compare shots from 70-300 that are cropped with my 500mm and see the difference. I am willing to spend the time necessary to learn how to get the most out of the lens. Did you try any macro shots with your 500mm and would you recommend attempting to do so ?

[reeftool]

Thanks for your advice reeftool. I will definitely compare shots from 70-300 that are cropped with my 500mm and see the difference. I am willing to spend the time necessary to learn how to get the most out of the lens. Did you try any macro shots with your 500mm and would you recommend attempting to do so ?

I tried a few but didn't have much success. My Sigma 70-300 has an excellent macro mode. I have since moved to using a K300/4 manual prime for most of my telephoto shooting but still use the Sigma for it's macro mode. It works very well shooting flowers and insects and things of interest from my kayak. The "macro" mode on the mirror is is several feet.

This is from the last time I used the lens, at the New York State Collegiate Rowing Championships in 2010. The lens now gathers dust.

[t.manning]

I haven't had my 70-300 long but from the few macro shots I have taken with it I am pleased. I guess having the "macro" mode on the mirror at several feet has its pros and cons. Thanks for that information.

[physoc]

I had a plan to buy a mirror lens as a cheapish 500mm tele. I'm very glad I didn't. What I did do was buy a x1.4 teleconverter (Kenko) that I can fit to my 70-300 telephoto. The advantages are huge. On a DX camera the x1.4 at 300mm gives me a 635mm equivalent crop compared with 420mm on a 35mm full-frame, full auto-focussing and image-stabilisation, even in poor light, easy handling compared with a bulky manual focus mirror lens, no shiny donut highlight rings, good contrast across the image and the converter will fit other lenses if I wish.

My impression, given the great number of second-hand mirror lenses that show-up on eBay, is that many people are buying a mirror lens and are then being disappointed. Am I disappointed with my Kenko Teleconverter? Oh no....

I've not tried any 'astro-photography' but I can't see why a mirror lens would have any advantage over a normal lens. Maybe people think that because it looks like a reflex telescope it's better fitted to the job?

[MPrince]

The best use I have found so far for my Spiratone 500mm mirror lens is as a doorstop.

It's not a very good doorstop, unfortunately.

[t.manning]

I had a plan to buy a mirror lens as a cheapish 500mm tele. I'm very glad I didn't. What I did do was buy a x1.4 teleconverter (Kenko) that I can fit to my 70-300 telephoto. The advantages are huge. On a DX camera the x1.4 at 300mm gives me a 635mm equivalent crop compared with 420mm on a 35mm full-frame, full auto-focussing and image-stabilisation, even in poor light, easy handling compared with a bulky manual focus mirror lens, no shiny donut highlight rings, good contrast across the image and the converter will fit other lenses if I wish.

My impression, given the great number of second-hand mirror lenses that show-up on eBay, is that many people are buying a mirror lens and are then being disappointed. Am I disappointed with my Kenko Teleconverter? Oh no....

I've not tried any 'astro-photography' but I can't see why a mirror lens would have any advantage over a normal lens. Maybe people think that because it looks like a reflex telescope it's better fitted to the job?

Thanks physoc for the input. I haven't bought the mirror lens so I will do some checking on converters and see if that might be a better option.

---------- Post added 03-03-14 at 01:43 PM ----------

Thanks MPrince. I would rather not waste my money on a non- functional doorstop.

[norfoot]

Hi all,
I am relatively new to photography and I am wondering what the pros and cons of a reflex- mirror lens are? I am interested in a Sakar 500mm F8 Reflex T Mount lens with a K mount adapter. What is the best use for a lens like this? Would this lens be good for astrophotography or macro shots ?

Thanks.

From my personal experience look at Tokina 500mm 8 or also Vivitat/Tamron or Sigma 600mm8. Most are pleased with theese lenses. A lens with T" adaptor can be easier to sell, but a fixed mount can sometimes work better. Some painted T2 adaptors need to have plack cote grinded off for camera electric kontact to lens. Use 1000 grade sand paper to get metal visuable for camera contact. If all lens move away from camera on focusing than Macro can be good. If lens fokus only with front or rear element or by mirror movement - than you teoreticly will get some contrast loss on close focus. Earlier days it was common also to mount a wideangle as 28/24 mm backwards, or also a 25 - 12 mm 16mm movie lens. This can give very good macro results but always depending on the lens optical quality. Zeiss Ikon did offer such lenses called Luminar for Contarex camera. In some cases if not to buy reverse adaptor - its easy to make it with a mount from an old lens or other adaptor + a filter ring + blue slow drying epoxy glue - but know what you are doing than ! ! Dont glue on camera.