+1. Mine too is silent.

You can check out the Tamron BB 500 mirror performance in a comparison thread I've just put up :

https://www.pentaxuser.com/forum/topic/garden-tests---da-300-vs-tokina-300-2-8-v...

Ha !

But ... 500mm, 1/15th handheld at ISO 12800

Lovely !

I have just acquired the Tokina 300/2.8 so wanted to give it a workout against my current 300-500 lens/TC combinations to see how it would stack up and when/if it would have an advantage over the DA*300/4 with or without the Tamron x1.4 and AFA x1.7. I threw the Tamron BB 500 Mirror into the mix just because I wanted to show some people how good this cheap lens can be if you can get past the occasional doughnut rendering of specular highlights !

So just down and dirty, these shots were taken the way I'd take them in the field (birding) and that means the DA*300 and Tokina 300/2.8 were used on a monopod (the Tokina especially is really just too heavy for handheld shots - though I did grab a few of a swallowtail butterfly that entered the garden just as I was packing up). The Tamron BB 500 was handheld - because currently in the field the DA*300 is on the monopod - so that is how I'd use it.

In all cases I kept the shutter speed at 1/500 and shot in RAW. And except for a few shots of some willing subjects at the end there has been no PP, i.e. no sharpening aside from when the RAW were imported into Aperture 3 and no Noise Reduction, but in a few cases I did use the auto-exposure and auto-curves button.

Note there is no systematical testing here - it's just what was of interest to me (and maybe someone else out there) !

So take of it what you will. If you like it then great ! If you don't think it's of any value then you can exit the thread and go onto another more interesting one. Hope this is of value to someone at least.

DA*300 vs Tokina 300 @ 100%



Tokina 300 + Tamron x1.4 @ 100%



B]Tokina 300 + Tamron x1.4 cropped vs AFA x1.7@ 100%[/B]



DA*300 + Tamron x1.4 equalised to AFA x1.7 @ 100%



DA*300 cropped to 500mm FoV vs Tamron BB 500 @ 100%



Tokina 300 at f4 and at f2.8 @ 100%



Tamron BB 500, out of camera and @ 100%




My test subjects, these shots have had minor PP (sharpened but no NR applied). The lens and TC used are written in Red on the shots




Tokina 300 @ f5.6, 1/500 and ISO 1,250



Proud Mama & Papa and their brood (there are 3 one is out of shot).



Tokina 300 + AFA x1.7 @ f5.6, 1/500 and ISO 500

[quote:3496ace15f="johnha"]I went for the mirror because I wanted to minimise CA (those pesky film days when you couldn't easily do anything in software) and at the time it was the only affordable option.
/quote]

Eradicate

I looked into this in detail and almost bought a Celestron. However due to the difficulties involved I am now contemplating buy a Pentax Q, a Q to K adapter and a Pentax Red Dot.

There is a guy on the other forum that has posted his set-up (actually more than one guy) and example pics - stunning ! Beauty of the set-up is that you can choose what lens to use and what mm you are looking for. The Q gives you 5.5. times the focal length of the lens in 35mm terms.

The shots posted with the 55-300 were very good (effective 1,650mm !) but I'm really waiting for the shots with his DA*300. However add this rig to a sharp 100mm and there is an instant 550mm - the perfect length for birding.

Of course you also now have a great little camera for other uses too.

All that said if you are buying the Celestron for star-work then ignore me !

The Sigma 10-20 F4-5.6 is a super lens. I use it almost exclusively when I'm shooting interiors (the 15 Ltd isn't wide enough). Great value for money but there is a noticeable amount of distortion that can not always be corrected in PP. Definitely sharp enough.

PTlens can correct distortion when needed sometimes in PP, but not always. However this is the nature of the beast and there isn't a WA out there that doesn't have some degree of distortion. If you want to avoid distortion in landscapes altogether then get a sharp 28mm, take multiple shots on a tripod and stitch.

BTW the 10-20 might be slow but on a K5 I have zero problems shooting in dark rooms (and I mean storerooms with no light but that from the doorway) ! Just find a point to focus on and recompose. Voila !

The 15 Ltd is a gorgeous lens, superb rendering and you would have to pry it from my cold dead fingers to get me to release it. It is a wonderful lens, but probably not wide enough for your needs.

Some excellent examples from both Steve and John above re. possibilities of 500/600 Mirror. The only real downside (if they bother you, and they do bother some) is the doughnut rendition of specular highlights. In most cases they don't bother me at all - and can even look interesting.

I have just come up from comparing 3 lenses and TCs in the garden (Tokina 300/2.8, DA*300 & Tamron BB 500, plus Tamron x1.4 and AFA x1.7). Again it was a pleasure to see the Tamron BB 500 perform well within it's capabilities even though with TCs I put the others on a monopod and used the Tamron handheld (because that's how I would use them in the field - birding).

I doubt with either of your choices you would lose money if you decide to buy to try and sell on if dissatisfied with the results.

BTW the Km is an excellent camera - it is limited in some ways but I've seen some wonderful shots from it.

This may be correct as there is no indication of sample size, but it still looks good and debunks the naysayers on these forums who complain about Pentax quality.

Thanks for posting this Opethian.