[Ash]

Sharp and reasonably workable with wildlife, this MF lens does well when in good lighting conditions.
Tamron 500mm f/8 mirror:

[barondla]

Nice mirror images everybody. Sometimes it is difficult to focus large telephoto lenses for reasons that have little to do with the lens. First, if the atmosphere is too turbulent, it may be impossible to get sharp pics. Focus is also affected by temperature change. As mentioned by others, a
Lens has to stabilize when moved to a different temperature.

Many large mirror users adjust focus to move mirror all the way back to the rear of the scope, for storage and transport. This guards against impact, but requires a bit more time to re adjust mirror to its standard focusing range.
Thanks,
barondla

[redpit]

Sharp and reasonably workable with wildlife, this MF lens does well when in good lighting conditions.
Tamron 500mm f/8 mirror:

This is nice! I love the mirror lens rendering. So different to all the "same looking" images

[edri]

KP+Alfo 300/5.6 Catadioptric Lens - approximate distance (googlemaps estimate) 1400 meters.

[jack002]

Had my Tamron 500 for a few weeks. I still struggle with focus! I think this was out a little

[mlynch53]

Was your Moon photo hand-held? I've realized that these mirror lenses need a tripod or at least a monopod, unless I'm shooting at a very high shutter speed in sunlit situations.

What mode were you shooting in? In some modes (maybe aperture priority?) my K-S2 will reliably give an in-focus indicator.

But practice, followed by more practice, is what these lenses require!

[marcusBMG]

Magnified live view is the way (depending on camera). IME focusing the tamron 500mm by eye at f8 (~ T10) with standard focus screen is inherently imprecise, even with the tenpa 1.35x OVF magnifier I use, even in best conditions (and forget it if its dull light). By eye use focus bracket techniques, eg shooting a short burst while slightly moving position (deiberate sway), or a quick sequence while touching the focus through the focus confirm signal point.

[jack002]

Was your Moon photo hand-held? I've realized that these mirror lenses need a tripod or at least a monopod, unless I'm shooting at a very high shutter speed in sunlit situations.

What mode were you shooting in? In some modes (maybe aperture priority?) my K-S2 will reliably give an in-focus indicator.

But practice, followed by more practice, is what these lenses require!

No, used a tripod, a 2 second self timer, a remote shutter.
I try to use the LV but its so over exposed I can't see anything.
After this I tried taking that clear filter off the back, and made sure the lens was completely clean

---------- Post added 12-06-19 at 09:13 AM ----------

Magnified live view is the way (depending on camera). IME focusing the tamron 500mm by eye at f8 (~ T10) with standard focus screen is inherently imprecise, even with the tenpa 1.35x OVF magnifier I use, even in best conditions (and forget it if its dull light). By eye use focus bracket techniques, eg shooting a short burst while slightly moving position (deiberate sway), or a quick sequence while touching the focus through the focus confirm signal point.

I have the K-5, using LV isn't working. Its way overexposed and I can't tell what I'm looking at. I also use the x10 in LV
I made a batanov mask, it doesn't seem to work.
The idea of doing a short burst while changing focus seems really difficult. The image shakes if I touch it even on a heavy tripod.

[marcusBMG]

I have the K-5, using LV isn't working. Its way overexposed

Try switching to spot metering, make sure the moon is centre frame. Or manual mode, set the exposure using lunar 11 rule.

[jack002]

Try switching to spot metering, make sure the moon is centre frame. Or manual mode, set the exposure using lunar 11 rule.

I am in manual mode, the Tamron is not an automatic lens, no other modes will work with it. I do use spot metering. The lunar 11 rule would mean I could set the aperture, its fixed at f8

[marcusBMG]

mmm thinking about it I think I did run into this problem too when I had my K5, I tended to use my samsung NX20 for moon shots at that time.

[rmcnelly]

No, used a tripod, a 2 second self timer, a remote shutter.
I try to use the LV but its so over exposed I can't see anything.
After this I tried taking that clear filter off the back, and made sure the lens was completely clean

---------- Post added 12-06-19 at 09:13 AM ----------



I have the K-5, using LV isn't working. Its way overexposed and I can't tell what I'm looking at. I also use the x10 in LV
I made a batanov mask, it doesn't seem to work.
The idea of doing a short burst while changing focus seems really difficult. The image shakes if I touch it even on a heavy tripod.

My understanding is the filters in the Tamron are part of the optical system, so the clear filter must be used if not using the color ones.

Some of your photos look unfocused and others look like lens or camera shake.

---------- Post added 12-06-19 at 01:02 PM ----------

I worked it out. Live view is how I do it now. This is what I did tonight

500mm f8 1/20th 80iso

Jack,

I think you might get better results if you raise your iso. There is a trade off here between shutter speed and iso.

[marcusBMG]

the filters in the Tamron are part of the optical system,

I've never been able to see any difference with the 500mm mirrors with or without the flter.
The 300mm f2.8's are also designed to be used with a filter. The main effect is to shift focus slightly - you may not be able to focus to infinity without the filter.

[jack002]

My understanding is the filters in the Tamron are part of the optical system, so the clear filter must be used if not using the color ones.

Some of your photos look unfocused and others look like lens or camera shake.

---------- Post added 12-06-19 at 01:02 PM ----------



Jack,

I think you might get better results if you raise your iso. There is a trade off here between shutter speed and iso.

Ok thanks, I will try that. Thank you all for your help. I hope to get this solved.

[cooltouch]

Exposure for the moon is very straightforward. Keep in mind, you're photographing a fairly bright light. The exposure I've always used, with a slight f/stop mod at times, is 1/125 @ f/8 @ ISO 100. The slight f/stop mod is to stop down to f/11. Often this results in better contrast. But obviously we can't do that with an f/8 mirror.

When I'm shooting the moon, I have to use the display to focus, but I don't always trust it, so I will refocus and shoot several times. Then in post production, I will compare the photos at 100% size and select the sharpest one. This usually gives me a good image.

The following is a color image. You can see the slight yellows and browns and blues in the moon's surface. Taken with a Tamron 500mm mirror -- the second version -- and a Sony NEX 7. 1/125 @ ISO 100.