[alfa75ts]

What did you use for the AF adjustment? I've never done my lenses, and the thought has always been back of the mind.

Homemade test chart. Tried chart clipped to clipboard, chart on foam framework etc, all inaccurate. Drew this up in cad and made it from 6mm mdf, printed on a laser printer. When the holes line up you are square-on at 45° no ifs or buts.

Note: The rear hole has to be centered at the height of the center line on the front as the front hole is drilled at a 45° angle.

Attached Images

View Picture EXIF

File Date

 

View Picture EXIF

File Date

   

---

Last edited by alfa75ts; 01-28-2019 at 01:29 PM.

[Canada_Rockies]

Homemade test chart. Tried chart clipped to clipboard, chart on foam framework etc, all inaccurate. Drew this up in cad and made it from 6mm mdf, printed on a laser printer. When the holes line up you are square-on at 45° no ifs or buts.

Note: The rear hole has to be centered at the height of the center line on the front as the front hole is drilled at a 45° angle.

Thanks, Craig! That's a project I think even my shop skills can handle.

[retneva]

I don’t see why there could not be such a club. The lens deserves it.

I dropped my DA* 300mm f4 recently on a hiking trip. The focus got stuck and it wouldn’t focus in either manual or autofocus mode. Somehow it fixed itself when I disassembled it this far.
It works again.
(Disassemble your own, at your own risk

[jacamar]

From a day trip from Santiago, Chile up into the Andes mountains - generally in order from lower to higher elevations.

Chilean Mockingbird




I hadn't encountered this bird family before - Grey-breasted Seedsnipe.





There were four chicks running around.




Rufous - collared Sparrow. Common just about everywhere.



Grey-headed Sierra-Finch



Best bird of the day - Diademed Sandpiper-Plover on its nest. They breed only above about 8,000 feet (2,400 metres) and are very vulnerable here. The dirt in the background is a tyre track about one foot from the nest.



Yellow - rumped Siskin - another high altitude bird



All K-3, DA*300mm with or without TC.

[marcusBMG]

Pleased to acquire one of these, especially with pka mount, and for an advantageous price. Pic 2 shows the tripod mount foot I had to diy cos' it was missing.
Now I can do a bit of acomparison of tokina 400's: tokyo koki 400mm f6.3 - the original; tokina rmc 400mm f6.3 (= soligor vivitar etc); tokina rmc 400mm f5.6 - the more compact modern design; tookina sd 400mm f5.6 - supposedly the optimum, = sigma apo... we shall see.

[traderdrew]

Both photos with the K-3 and the Sigma 500mm F/4.5

[WPRESTO]

Pleased to acquire one of these, especially with pka mount, and for an advantageous price. Pic 2 shows the tripod mount foot I had to diy cos' it was missing.
Now I can do a bit of acomparison of tokina 400's: tokyo koki 400mm f6.3 - the original; tokina rmc 400mm f6.3 (= soligor vivitar etc); tokina rmc 400mm f5.6 - the more compact modern design; tookina sd 400mm f5.6 - supposedly the optimum, = sigma apo... we shall see.

I used one of those Tokinas for several years back in the film era. I especially liked it's compact size and the slide-forward lens hood (there should be a law requiring such a hood on all lenses of 100mm and longer). I found the lens too soft at f5.6, but decent @ f8~9.6.

[traderdrew]

I believe this is for aligning the camera with the lens. 45 degrees isn't necessary. In fact I'd rather have a steeper degree and that way you spread out the length of the depth of field. I had a discussion with Michael Tapes about this. He is the inventor of lens align. He told me everybody wanted 45 degrees and so he had to design one with that angle. I think he told me a 35 degree angle is what he uses but I'm not sure.

[Canada_Rockies]

I believe this is for aligning the camera with the lens. 45 degrees isn't necessary. In fact I'd rather have a steeper degree and that way you spread out the length of the depth of field. I had a discussion with Michael Tapes about this. He is the inventor of lens align. He told me everybody wanted 45 degrees and so he had to design one with that angle. I think he told me a 35 degree angle is what he uses but I'm not sure.

Thanks. That is an interesting thought and makes a lot of sense.

[alfa75ts]

45 degrees isn't necessary. In fact I'd rather have a steeper degree and that way you spread out the length of the depth of field.

True, what is important is keeping the DoF within the depth of the target. If you keep your DoF fairly tight (say a little less than 25mm/ 1") on my chart, then at 45° it is quite easy to see any changes when reviewing the image on the camera.

Using the alignment holes adds consistency allowing you to compare results taken during different tests.

[alfa75ts]

An interesting but somewhat frustrating morning.

The Swamp Harriers came out to play. Four of them practicing hunting in the middle of a field. I think mom would make a kill and then encourage the youngsters to practice on it.

The setup: Me, 15 metres of potentially snake infested reeds a metre high, a row of trees, 60 or 70 metres of long grass, the harriers, 100 metres of short grass, and lastly, thick trees.

So I was only getting glimpses of them through gaps in the nearby trees and the trees at the rear were making AF nearly useless. MF was tough as were circling.

[dbs]

They look good under the circumstances
Me I am too slow with manual focus and auto ....well..the trees are sharp..


Dave

[traderdrew]

True, what is important is keeping the DoF within the depth of the target. If you keep your DoF fairly tight (say a little less than 25mm/ 1") on my chart, then at 45° it is quite easy to see any changes when reviewing the image on the camera.

Using the alignment holes adds consistency allowing you to compare results taken during different tests.

Alignment holes are essential and lens align designs incorporate these. Another way of explaining what I was trying to say. You can think of this using various angles of various degrees and it won’t make a difference to the camera. A shallow degree angle would be worse because there isn’t much room for the depth of field to show. I’d rather use a 35 degree angle than a 45 if I’m using a small alignment device like lens align. I will always shoot at the widest aperture also. One of the weird things is that the camera will have different alignments at different distances. I thought I had my teleconverter alignment done but I was photographing ducks with it on and I was almost always constantly off. I figure it was because the distance was much further away from the distance of alignment. I suspect if the camera was off one way and the lens was off another (one back focused and the other front focused), how can an alignment fix that? It would be best to send one of the two back for fine-tuning. A Nikon guy told me he sent a lens back three times and finally they got the alignment right. He said “they didn’t listen to him”

[alfa75ts]

Back to the K3 today.

Must say that AF-C is much more decisive on the K7, the K3 has trouble making up it's mind as to which focus point is better. I can't say which camera is more accurate.

A bit of variety:

Rainbow Lorikeet in the early morning sun.



Magpie Lark



Swamp Harrier



Black-shouldered Kite



Australasian Bittern



Brown Falcon (a bit of a surprise when I got home, I thought it was another Swamp Harrier )



Brown Falcon (top left) with Swamp Harrier (bottom right)



And just for the heck of it, trees in background out of focus + heat haze.

[dbs]

Hi Craig

That last one looks like one of my efforts at bif....where's the bird where's the bird....

Dave