Agrostemma

Joined: 9th September 2014

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Agrostemma
The trees have already came into leaf, the grass is green too.

Is anybody tempted to open the world in light not completely visible to human eyes?

If so, the cameras are still on sale. I can provide some more photos side by side (the same scenes) done in the 9th of April, the trees were just in their buds, this time I have included the version straight from the camera (UNIWB), as well as AutoWB in raw converter. Please, send PM and I'll give you Google disk link.

And on the occasion of greenery around us the prices are reduced as well:

*istD infrared - £154
K-r infrared - £182

Comment by Agrostemma posted on Two infrared converted Pentax bodies for sale at 03/05/2019 - 10:00

Agrostemma
Now price reduced:

*istD infrared -£168
K-r infrared -£192


The cameras are still in Lithuania. If anybody is interested to try them and inspect on site in UK, both or one of them can be carried to Kingston upon Thames, KT2 by the middle of August.

Postage anywhere in EU is also possible, I think it will be around £15-20.

Please, ask here or send PM if interested.

Comment by Agrostemma posted on Two infrared converted Pentax bodies for sale at 23/07/2018 - 13:55

Agrostemma
Price reduction:
*istD infrared -£180
K-r infrared -£205

Comment by Agrostemma posted on Two infrared converted Pentax bodies for sale at 28/05/2018 - 12:01

Agrostemma
Here is the sample from K-r with DA 21 lens (not HD, the same lens as used for taking second photo from *istD):

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The tree is colourful it is autumn it was yellow, might be it will be not so blue in spring, aperture is F8, no hotspot.

Comment by Agrostemma posted on Two infrared converted Pentax bodies for sale at 16/05/2018 - 17:41

Agrostemma
Here it is the same basketball scene taken with K-r. And HD DA 35 f2.8macro. With f 8. Never thought it gives hotspot, but it does. A bluish hotspot (in unswapped channels). Partly it is manageable to eliminate the hotspot converting to BW and suppressing blue channels in luminance equalizer. Nevertheless in spite of hotspot I think you can see the colourfulness difference between to cameras (colours always are untouched, only WB in RawTherapee is set to 'Auto').

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Comment by Agrostemma posted on Two infrared converted Pentax bodies for sale at 16/05/2018 - 17:24

Agrostemma
Here are the photos of *istD (I think the photos of K-r is not necessary, as it is not rare). In the second photo you can see the custom white balance option chosen, and the first one of custom is UniWB saved before the conversion.

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The lens attached is Vivitar 28mm f2.8, nothing special, not for sale.

Comment by Agrostemma posted on Two infrared converted Pentax bodies for sale at 16/05/2018 - 16:21

Agrostemma
Here are few samples from *ist-D with: kit lens, 21 lens and FA-35 lens. First sample channels intact, second sample channels swapped.Comment Image

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I have the photos of the same third scene made with K-r, I'll search for it and post later.

Comment by Agrostemma posted on Two infrared converted Pentax bodies for sale at 16/05/2018 - 14:19

Agrostemma
After adjusting auto white balance of the photo in RawTherapee difference between the cameras is that with the *istD (sensor and 720nm filter) there is very little of remaining colours, blue and red channel swap does not give the colour to the sky (especially with the kit lens, with 35 FA you get more colour), the sky remains almost in grey tones, with the K-r (sensor and 680 nm filter combo) you have more colours and red-blue channel swapping gives blue colour to the sky, and reddish colour to the trees. I think the colourfulness might depend on the weather as well, as it might be slightly different ratio of VIS-IR rays, or slightly different spectre of IR in different conditions.

Also, exposition measuring works only approximately, taking photo with the sunny side of the sky you have to add +2--3 exposition compensation, without the sun you have to add +0--1

Comment by Agrostemma posted on Two infrared converted Pentax bodies for sale at 16/05/2018 - 12:46

Agrostemma
I am selling two of my infrared converted Pentax camera bodies. The cameras were converted in Lithuania by an electric engineer who converts various sorts of cameras to IR. I leave my old K-x converted to IR 680 nm for myself.

For sale:

Pentax *istD, converted to IR with 720 nm filter. I bought it second hand for conversion. Shutter count (actually named ‘frame number’) now is 36623. Focusing works rather well with the fixed lenses, but not so well with zooms. I have never tried adjusting focus via service menu (though successfully did this for my K 100d Super and K-x), for *istD it might be possible as well, but I decided it was too complicated for me.
*istD infrared in original packaging+ 4GB CF card. Asking price £190

Pentax K-r, converted to IR with 680 nm filter. It was my wife’s camera before conversion. During usage before conversion the diaphragm module got faulty and was repaired under warranty. Focusing works well, also there is focus adjustment option in the user menu. Shutter count now is 5046
K-r infrared in original packaging with battery and charger. Also + original AA Battery Holder-Adapter D-BH109. Asking price £230.

Both cameras are with UniWB white balance presets (this you can do in K-r at any time completely underexposing the photo), but with the *ist D I created this preset before conversion taking a picture of special magenta screen.

Collection from Kingston upon Thames, KT2 after the 1st of June.
Cash on collection preferred but will consider posting (then + delivery costs) if paid via paypal (‘friends, family mode’ I think).
Inspection is welcome before committing to buy.

Comment by Agrostemma posted on Two infrared converted Pentax bodies for sale at 16/05/2018 - 11:54

Agrostemma
I can share my experience using Tokina AT-X 28-70mm-f2.8 with K-1. It is the first version of these Tokinas, the one with light orange marking ring and 72 mm filter thread. I bought it long ago and occasionally used with K100d super as fast zoom. Later, with K5II I almost never used it, as 20-40 was sufficient and more convenient zoom for crop.

Now I too didn’t buy Pentax 24-70mm together with used K-1, mainly due to the size, as price for used lens was rather good.

Tokina AT-X 28-70mm-f2.8 is not optimized for digital but in certain conditions works well.

Advantages:
compact for a 2.8 fast lens;
sharp in 28-45 mm range from the f 2.8;
pleasant bokeh (not with any special character, but without any annoyances).

Distavantages:
in 50-70 mm range sharp only from f 4 (especially 70mm)
suitable only indoors, if outdoors, only in cloudy weather. Bright sky, especially the sky side with the Sun is no-go for the lens, contrast drops significantly;
my item doesn’t focus well to infinity at 28 mm. Infinity focus in 29-30 mm is OK.

Comment by Agrostemma posted on Standard zoom options for the K1 at 15/05/2018 - 13:55

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