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Forum: Pentax Camera and Field Accessories 04-11-2020, 12:50 PM  
KENKO 12mm Macro Extension Tube - Aperture not actuating on digital cameras?
Posted By tryphon4
Replies: 10
Views: 548
If you want to keep electrical contacts between lens and body, you should search a KA extension tube, like the one below (the middle one):




It is not very easy to find and it is not cheap.
Forum: General Photography 04-04-2020, 12:33 AM  
CS mount varifocal CCTV lens usage in photography.
Posted By tryphon4
Replies: 5
Views: 370
A C-S lens could be used on a Pentax Q, the problem is to find a "C-S lens to Q" ring adapter.
There are plenty of "C lens to Q" adapters but I never found a "C-S lens to Q" one on €bay.


C mount register is 17.526mm, C-S mount register is 12.526mm, Q register is 9.2mm.
Camera Mounts Sorted by Register

You may want to 3D-print a custom adapter, then there is a useful link : C & CS Lens to PENTAX Q mount adapter by nameless911 - Thingiverse
Forum: Monthly Photo Contests 04-02-2020, 01:14 PM  
Tyrannus under the rain
Posted By tryphon4
Replies: 3
Views: 110
I would like to nominate this photo
Forum: Pentax SLR Lens Discussion 03-29-2020, 10:01 AM  
"Macro" zooms
Posted By tryphon4
Replies: 16
Views: 1,279
Do not trust the name. There is no real macro zoom.
Macro means: able to shoot at 1:1.

Nikon used to produce a "near macro" zoom (70-180mm 1:1.3), decades ago.
Olympus may have produced a macro zoom decades ago, I am not sure.


However, you can find some "proxi" zooms, they reach 1:2 (e.g. 70-300mm from Tamron or Sigma).
Then you can add some stuff (teleconverter, diopter...) to eventually reach 1:1.


In fact, most macro lenses are false zooms (their focal length varies according to the macro ratio) but this information can be confusing for most people.
Forum: Flashes, Lighting, and Studio 01-09-2020, 02:10 PM  
Flash for GR iii
Posted By tryphon4
Replies: 7
Views: 968
My old Sigma EF 530 DG Super (Pentax hot shoe) works fine with my brand new GR III, it is great, the drawback is the flash's size which is bigger than the GR's one! :D
Forum: Photographic Technique 12-29-2019, 09:21 AM  
Macro Another Macro option
Posted By tryphon4
Replies: 15
Views: 974
Cheap magnifying lenses give crappy results. If you want to get sharp photos, you shall use achromats containing at least 2 elements. There is a useful list here: Index.

I own some excellent achromats (Nikon 5T & 6T, Raynox DCR, Sigma life size converter, Lomo AL-4) and some bad ones (Marumi DHG, Olympus MCON 35).
Forum: Digital Processing, Software, and Printing 12-21-2019, 01:16 AM  
Pixelmator Pro Enlarging
Posted By tryphon4
Replies: 4
Views: 568
This looks interesting but I'd prefer photozoom pro. I look forward to seeing a comparison between Pixelmator and leaders (photozoom, wondershare, onone).
Forum: Photographic Technique 12-18-2019, 11:09 PM  
Macro Another Macro option
Posted By tryphon4
Replies: 15
Views: 974
Taking video frames is not silly at all. I've already considered this possibility. It could be achieved, thus the camera movement should be smooth (no vibrations means heavy setup) with stops at intervals (the Stackshot system, by Cognisys, can be an excellent motor-driven setup), in order to have sharp frames.
Forum: Photographic Technique 12-18-2019, 02:49 PM  
Macro Another Macro option
Posted By tryphon4
Replies: 15
Views: 974
Indeed! I would love to avoid focus stacking, because this technique is a pain for the shutter. I am looking forward having a global electronic shutter on my DSLR!
Forum: Photographic Technique 12-18-2019, 11:23 AM  
Macro Another Macro option
Posted By tryphon4
Replies: 15
Views: 974
It can be useful to remind the basics: We have few means in order to increase magnification:
1. increase focal length thanks to a teleconverter.
2. decrease focal length.
3. increase the "lens to sensor" distance without decreasing focal length.

Solution 1 is practically limited to 2x teleconverters, and if you want to keep full sharpness you should limit to 1.7x (it depends on the lens sharpness and teleconverter sharpness).
Solution 2 is achieved with long focal lenses and diopters (a diopter and a reversed lens are mostly the same thing). This solution may not be a good idea with a short focal length lens because when you decease the focal length, you also decrease the working distance and the latter may tend to zero.
Solution 3 is achieved with bellows, extension rings, helicoid rings, etc. It is easier with short focal length lenses because the needed extension is proportional to the focal length.

You could mix solution 2 and 3: decreasing the global focal length and increasing the "lens to sensor" distance.
Remember one more thing: the focal length of a lens is true when focused to infinity. Most lenses have variable focal length, for example my Tamron 90mm macro, at 1:1, is in fact a 75mm lens. My Irix 150mm, at 1:1, is in fact a 90mm lens.

At the end of the day, you will find that long working distance = long focal length. It is just mathematical.



You can reach 1:1 with a Rodagon 135mm using a 21.75 cm extension ring, the working distance is huge: 26.25 cm (see photo above).
You can reach 1:1 with a Rodagon 105mm using a 16.25 cm extension ring, the working distance is big: 19.25 cm.
You can reach 1:1 with an APO Rodagon 50mm using a 5.75 cm extension ring, the working distance is short: 6.75 cm.
Forum: Photographic Technique 12-17-2019, 11:08 AM  
Macro Another Macro option
Posted By tryphon4
Replies: 15
Views: 974
Well, it does not look so different from what is commonly used by macro fans.

For example, in 2011 I used this setup: Pentacon six lens (80mm F/2.8) on a "PK to Pentacon six" tilt adapter, step-down rings, reversed enlarger lens (Componon 28mm F/4)



You can easily reach 8:1 and more with that kind of setup, what is important is to use very good optics (sharp). In this case the Pentacon was not so good, using the reversed 28mm on long extension rings was preferable :)
Forum: Pentax News and Rumors 12-16-2019, 02:50 PM  
Mitakon 85mm 2.8 1X to 5X Macro Lens $499
Posted By tryphon4
Replies: 48
Views: 3,417
Mitakon discovered a quality concern regarding the lens:






QuoteQuote:

IMPORTANT NOTIFICATION (16th Dec): We have recently found that the first shipment of our 85mm f/2.8 is not performing to our design specifications. We are now investigating the issue and its not available to order now. For all purchased customers, we have already sent out an email to the mailbox address you left in the order details. Please contact us via order@zyoptics.net if you have NOT received such email.



Fortunately, Mitakon already found the solution and built a new prototype, so they should be able to deliver the updated lens in January.
They are very responsive!
Forum: Pentax SLR Lens Discussion 12-11-2019, 11:53 AM  
Pentax macro lens
Posted By tryphon4
Replies: 44
Views: 1,774
And "internal focusing" means "focal length decrease", so the minimum focus is 55cm for the A* and 51cm for the FA*.

Size matters :)
Forum: Pentax News and Rumors 12-03-2019, 02:20 PM  
Mitakon 85mm 2.8 1X to 5X Macro Lens $499
Posted By tryphon4
Replies: 48
Views: 3,417
This lens seems to be very interesting!

The announced working distance at 1:1 (230mm) is similar to the Sigma 180mm macro F/3.5's working distance, huge!
The announced working distance at 5:1 is stellar: 95mm. For information, the "famous" Canon MP-E 65's working distance at 5:1 is 41mm only!
In fact it is hard to believe.
Forum: Pentax SLR Lens Discussion 12-01-2019, 11:07 PM  
Pentax macro lens
Posted By tryphon4
Replies: 44
Views: 1,774
The Laowa 24mm probe is not a common macro lens but a very specialized one, its best speed is F/14!
It is intended to shoot small fishes in a tank or in a river.
Forum: Pentax SLR Lens Discussion 12-01-2019, 08:00 AM  
Pentax macro lens
Posted By tryphon4
Replies: 44
Views: 1,774
The working distance is an important characteristic from my moint of view, because insects can be very shy.

You can find below some working distances at 1:1, in centimeters:

(http://hlaville.free.fr/MMP/regle_macro.png)
As it is in French, I have to translate a point: the Vivitar 135mm Close Focus (real 135mm, reaches 1:2 alone) is here used with an extension ring set (650mm added), it is impressive but hard to use because it becomes a bazooka (see below, the last lens).

(http://hlaville.free.fr/images/150macro/_1150019.jpg)
Forum: Pentax SLR Lens Discussion 12-01-2019, 07:41 AM  
Pentax macro lens
Posted By tryphon4
Replies: 44
Views: 1,774
The original 60mm F/2.8 2:1 macro lens is made and sold by Venus-Laowa.
However, there are copies of this lens with almost the same shape, they share the same optics and are sold under other brands: Oshiro or Bresser.

According to Laowa, the Oshiro's and Bresser's 60mm are copies, but I have no proof of that. The price is lower for the (potential) copies so I bought a copy (mine has no brand at all but the shape is the same than the Bresser).

Here is the Laowa:


Here is my "copy":


The common characteristics of Laowa, Oshiro and Bresser are:
- No "A" position on the aperture ring: If you set an aperture of F/16, you will compose your photo and focus at F/16, not wide open (and it may be difficult if you have no pilot lamp).
- 14 blades aperture
- same weight, height, diameter: about 500g, 70x95 mm
- same optics (9 elements, 7 groups)
-same minimum focusing distance: 18cm


This is the Venus-Laowa user review section: Venus Optics Laowa 60mm F2.8 2:1 Ultra Macro Lens Reviews - Venus Laowa Lenses - Pentax Lens Review Database

The Kuangren Kx 800 flash is compatible with any Pentax camera. It is fully manual: you separately adjust the power of the two heads.





It contains a led pilot lamp (with variable power), this pilot lamp is hugely useful when you close the aperture at F/8 and beyond.
Forum: Pentax SLR Lens Discussion 12-01-2019, 04:39 AM  
Pentax macro lens
Posted By tryphon4
Replies: 44
Views: 1,774
I am not sure about your question: Do you ask what is the best lens among those you have listed or what is our best macro lens ever?

Then the answer depends on your purpose: do you plan to shoot flowers, insects, more often at 1:4 or 1:2 or at 1:1 and beyond?

If you plan to shoot at magnifications between 1:1 and about 5:1, the choices are different.

I will answer for lenses between 1:2 and 1:1 (for enlargements up to 2:1, the Bresser/Oshiro 60mm macro F/2.8 is excellent).

I owned many macro lenses, some are interesting for their sharpness, other for the bokeh, other for the background.

Longer focal lenses deliver very creamy and seamless background but they need higher speed. I love my Sigma 180mm F/3.5 but most of time I have to use a flash with it (I love my full manual Kuangren K-X 800 macro flash). My Irix 150mm is excellent too but less when wide open.


90mm to 100mm are probably the more powerful focal lengths, not too high and not too low.
The different Tamron 90mm are all excellent (I owned a 52B, it reaches 1:2 but is interesting for the bokeh, then a 72B that was excellent but MF, now I own a 272E which is the same as the 72B except for the AF).


I think that the best macro lens is perhaps the Pentax DFA 100mm macro WR, it is wheather sealed and its working distance looks useful.

The F, FA and DFA 100mm macro share the same optics, the differences are regarding sealing and quick-shift.
Forum: Pentax SLR Lens Discussion 07-29-2019, 08:48 AM  
Pentax-FA 100mm SMC f/3.5 Macro
Posted By tryphon4
Replies: 8
Views: 1,045
I owned this lens (mine was AF and Cosina branded), it was my first macro lens.

It reaches 1:2 alone, and 1:1 using the provided diopter. The diopter quality is good: it is an achromatic one.
The image quality is not in par with the quality delivered by a true macro lens (Pentax 100mm/2.8, Tamron 90mm/2.8, Sigma 105mm/2.8 etc.) but it is a bargain if you can cope with the noisy AF, the cheap-looking plastics and the long focus throw.
On top of that, the working distance is quite interesting: about 13cm.

More info here: Cosina ( Vivitar etc) 100mm F3.5 MC Makro Lens Reviews - Cosina Lenses - Pentax Lens Review Database
Forum: Flashes, Lighting, and Studio 05-31-2019, 02:01 AM  
Looking for twin macro light bracket
Posted By tryphon4
Replies: 10
Views: 763
There is actually a LCD display on my KX-800, as you can see abobe:



I see no evidence of a new model, in fact I suppose that the first KX-800 (years ago) did not own this LCD display.
Forum: Flashes, Lighting, and Studio 05-28-2019, 01:15 PM  
Looking for twin macro light bracket
Posted By tryphon4
Replies: 10
Views: 763
I bought a Kuangren K-X 800 macro flash (single hot-shoe mounted power units with two flexible arms), it is full manual but extremely versatile. Now this is the only flash setup I use in proxi & macro. The continuous LED light improves manual focusing, then the two-heads flash is adjustable by 1EV step for each head.

Forum: General Photography 04-27-2019, 05:38 AM  
3d effect
Posted By tryphon4
Replies: 11
Views: 878
Do you speak about this photo?


It's been bought on Fotolia.

Anyways, let's focus on your problem.

3D effect is given by the lens, depth of field shall be thin but sufficient, background shall be far away, bokeh shall be creamy.

Smoke can be simulated by many photoshop actions, brushes and plugins.
Corel particleshop is an excellent plugin that enables painting with fire, smoke, fireworks etc.
You also can check this link: Real smoke plugin photoshop brushes download (22 photoshop brushes) for commercial use. format: abr
Forum: Pentax Medium Format 04-26-2019, 05:44 AM  
FA 4/300 with M8 tripod mount - bizarre
Posted By tryphon4
Replies: 12
Views: 1,321
Your M8 thread looks like an helicoil. This kind of insert is easy to put in but very difficult to remove.
Forum: Lens Clubs 03-05-2019, 01:43 PM  
*Macro* lens club
Posted By tryphon4
Replies: 3,864
Views: 512,322
Irix 150mm F/2.8 macro:


exif


exif
Forum: Pentax SLR Lens Discussion 03-04-2019, 02:05 PM  
FA 100mm f3.5 or D-FA 100mm f2.8 (non WR)?
Posted By tryphon4
Replies: 18
Views: 1,401
I had a 100mm f3.5, in fact it was not Pentax branded but Cosina.
This lens has been sold under many different brands, it is called "cream in a yoghurt cup".
It was my first macro lens. In reality it reaches 1:2 alone, and 1:1 with a specific close-up.
It is "all plastic", looks cheap and the AF is very noisy. It is not a beautiful lens.



It is a rather good macro lens (in terms of image general sharpness) but definitly not it the same league than DFA 100mm F2.8, Sigma 105mm F2.8, Tamron 90mm F2.8, Sigma 180mm F3.5, Irix 150mm F2.8, etc. Even the old Tamron 90mm F2.5 (adaptall mount) is way better.
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