What's your latest acquisition?

Very Nice, lens and image

Testing out the sharpness of the M 400mm f5.6 with the K3iii now that I have fitted a UV filter to try and reduce the problem with CA. Impressed with the results.

Slight crop of pigeon




Original and heavy crop of greenfinches

Last week I picked up a Sigma 35mm f/2 DG DN in L mount. It's a beautiful lens - very solidly made, real aperture ring and excellent optics.


IMG_5652 by Jonathan MacDonald, on Flickr

Just purchased a Pentax-D FA 15-30mm f/2.8. Sold mine a while back and never really gave it a chance so hopefully I will this time. Still have a couple of filters and a holder for it somewhere I think.

Got a few more lenses to sell and looking for a 70-200mm f/2.8 or maybe the 70-210mm then I'm done for now.

I bought a cheap FAJ 75-300mm online as I don't have anything decent longer than 105mm these days in KAF mount and I thought I'd give it a go. When it arrived the (plastic) mount had been smashed, most likely in a nasty camera fall. It couldn't even be mounted on a camera! Even Cash Converters must surely pay some basic attention to what they're buying and selling.

It's going straight back, obviously.

You got the name of the shop wrong Jonathan - it's clearly Crash Converters

If you want something along those lines you can't go wrong with the SMC Pentax-FA 1:4.5-5.6 80-320mm. They tend to hold a slightly higher price than most of that vintage but it's justified. They work smoothly, have nice colours and will support huge crops, even at the long end.

Today i bought a Nisi HUC CPL in 72mm(a polariser) from Cfiphoto.com
Guess what? the warehouse that sells the Nisi equipment online worldwide is a twenty minute walk from where i live and i could collect it at there door
i also bought a few adapter rings i need for other lenses
Then i decided to purchase the Nisi V5 pro 100mm system filter holder kit which includes its adapter rings and polariser for the knock down price of 80 Euros.
just shy of 200 euros spend in total and now i have to get the Grads and NDs to complete the set up.
Another fortune to spend maybe in a few weeks time but Darren the chap i was personally dealing with said, there's a price hike coming in the glass filters as in very soon.
Still happy with the deal and the chat.

My second copy of the Tokina 17mm f3.5 arrived today. My fault the first one was damaged

It's an acquisition, but a gizmo cobbled together from bits and pieces rather than a purchase. Here's the story...

Having recently got a Laowa 25mm 2.5 - 5x macro lens, it was now necessary to be able to move the camera in 50 micron (0.05mm) steps for focus stacks in order to take full advantage of the 5x magnification. I use Novoflex racks (manual, not the £2K automatic!). From the scale on the rack and the standard knurled knob (see below), steps of 1mm are easy, 1/2 mm fairly easy, approx 1/3 mm (333 micron) with a good eye, a steady hand and lots of patience.




With the Novoflex fine adjustment knob attached (see below - costs more than you think it should), each tick is a movement of 1/4mm, 1/8mm is fairly easy and approx 1/12mm (0.083mm, 83 micron) is just about possible with a good eye, a steady hand, and a lot of patience. Nearly 50 micron, but not quite.




I use crossed racks, one forward/back for the stack, the other for sideways alignment (get it right, then leave it). So I wondered whether mounting a protractor on the fine adjusment knob for forward/back motion and a pointer on the stationary, cross-mounted rack would give me finer gradation (a nod to member Coker here, he once mentioned that he does that with the focus ring of a lens to get fine focus steps).

A quick feasibility study showed promise, so in true Blue Peter fashion I knocked up a gizmo from scrap aluminium, a plastic lid from an old margarine tub, a scap of old cloth, a bit of garden wire, cardboard, rubber bands, a small torch and a 1/4 inch screw. It works. So here it is (see pictures below). The angle turned is read from the shadow of the pointer on the protractor. This eliminates the perspective error that arises when simply looking at the position of the pointer itself. Turning the protractor by 1 degree gives a movement of 1/24 mm (42 micron), which is what was needed .













With a good eye, a very steady hand, lots of patience and not breathing, about 1/2 degree (1/48 mm, 21 micron) should be achievable. However, at that point I'd start wondering about how accurate the mechanical movement of the focus rack would be .

And in case anyone is wondering, the stand holding the racks in the pictures is just for convenience here. For focus stacking, the racks would be mounted on a rock solid geared head attached to a rock solid kitchen surface by a big and very solid clamp.

If nothing else, making this gizmo was a good way to while away the time during days when it has been too hot to do much else...

Steve

I do like your sideways thinking regarding the shadow on the protractor.

Thanks. I'd like to say that the shadow on the protractor works perfectly, but during a try out yesterday a problem emerged. Nothing wrong with the shadow, it's my eyesight that needs fixing - you need to be close to the protractor be able to read the fine detail but my glasses are set for normal reading distance. I'm now on the lookout for a suitable magnifying glass .

The try out was an attempt to find the limit of the possible by trying a stack of the stigma of a tiny flower (marjoram) at 5x magnification - estimate 1/3mm from front to back. It was a good learning exercise. And I think it pushed manual control of a rack and pinion focus rack to the limit, even the excellent Novoflex one. Anything further would require a good worm .

Steve

Latest acquisition for me is a Kiev 4 with a Jupiter 8 50mm f2. The shutter seems broke so needs to be sent off for repair somewhere but the camera looks brand new so I was happy to buy knowing this.

I got a faster 128GB SD card as I got a bit tired of waiting for the camera to write when shooting in burst mode, which I do more these days.

My latest acquisition is a broken pair of Mrs L's old reading glasses, kindly donated by Mrs L as a contribution to my increasingly sophisticated macro rig (original as per post on 12/08/2022). They are now mounted so that I can easily and accurately read the position of the pointer (shadow) on the protractor scale from a comfortable sitting position. See picture below. A fine example of upcycling, repurposing, creative reuse or whatever we are meant to say nowadays. And also a fine example of not throwing anything away if it might just be useful sometime, even if you can't imagine how and when .

This latest upgrade to the rig has also included replacing the cardboard backing for the protractor disc by a CD. It turns out that CDs are just the right size and a lot stiffer than cardboard.




Steve