new adaptors
 

Hi guys,

Dennis at Brevis (how poetic) has sent me two new Brevis adaptors to replace mine, with new tweaks on them. I will get them tomorrow and will let you know how well they perform. I am sure very well!

Also a chap in Brazil called Adriano has sent me one of his new adaptors called the Apefos...again this should come tomorrow...I will let you guys know what I think!

Phil

Apefos' website... interesting, but the images look rather grainy.

VERY dissapointed with the Apefos.

Initial impressions...

Solid, but probably as well made as the Letus rather than the Redrock or Brevis.

Terrible plastic thread, coming off already. Non lockable Nikon Thread, not as bad as my old Letus but pretty atrocious!

Worst of all...It gives some sort of Vortex BOKEH. Never a good look.

Adriano the maker is looking into this for me. I am hoping he can fix it, he thinks there could be something wrong with the vibration. I like the image otherwise.

Have a look below. 3rd image is brevis

Phil.

RE: APEFOS.

Is he oscillating an entire fresnel condenser/groundglass combination? This might account for the circular effect and that could be a dead-end for ultra-wide shots where there are more defined textures in background.

If he is using an inertial resistive action like Quyen, he may be getting a static or slow centre. I would expect to see grain in or near the centre if this was happening. It will be interesting if you increase the shutter speed, tighten the aperture and see where the grain shows first.

I really don't know Bob. Adriano is trying to work out the problem, he thinks it is vibrating in a circular motion and he trying to find out why...problem him being in Brazil makes it difficult.

Could it be the achromat? I don't think he has ever tested it with an achromat...could this cause such a look?

Phil.

It mght be related to the achromat if he has another element in there as a condenser.

I have seen something similar when I was setting up the telescope eyepiece optics on an earlier version of my own project, but there was also a darkness area associated with this abberation. Edge distortion as a radial stretching effect around the perpihery of the image is something we often see here.

If there is a correcting element in there interacting with the achromat, then a radial compressing optical effect might occur which would create the artifact in the APEFOs image. If you are able to zoom in a little closer, it may go away but this then defeats the resolution quality of the image.

The image to my eye otherwise would be acceptable.

its the condenser...it creats the vortex when wide open.

Adriano's solution...remove the condenser, which means it would be wide open to all the elements...not good...other solution dont make stuff out of focus in background then you wont see it!

Phil.

There was a reference to the Apefos here a while back. I suggested then, that except for misgivings I felt about some build issues, that it should not be dismissed too lightly.

If SLR lens aperture affects the condenser interaction, then is the condenser between the SLR lens and the GG???

If the condenser is on the camcorder side of the GG and is simply moved closer to the achromat, some of the distortion may go away.

Another solution might be to use a wider diameter condenser of same or maybe a little lesser power that the achromat/camcorder combination can zoom inside of without having to claim too small an area off the groundglass.

A wider diameter condenser in turn may require a wider diameter case and if that is the situation, there comes another problem.

That is the elusive nature of R&D even if it is effectively reverse engineering.

Phil, who is the hot chick? :-)

that's my woman!!

I figured a daughter or something. :-) My wife also has brown hair and eyes..

Ha ha! i would have had to have started at 5!! even in this day and age and wee bit early!