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Forum: Pentax SLR Lens Discussion
04-11-2011, 12:25 AM
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Yes it is an Adaptall ("without-2") system lens, CT-135 from 1976-79:
Tamron Adaptall Series Lenses
And yes, you can use your Adaptall-2 Custom Mount for Adaptall lenses also. In fact, Adaptall-2 mounts are said to be mechanically much more reliable than the Adaptall mounts.
And, by the way, I have seen quite a few pictures taken with this 135/2.8 lens. It appears to be a fine optical performer.
B.R. / Steen G. B.
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Forum: Pentax Camera and Field Accessories
08-09-2012, 06:22 AM
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There have been a few recent threads about "Astrotracer Troubles" so, I would like to show some results with my fairly long Tamron Adaptall-2 SP 350mm f/5.6 (Model 06B) lens.
I have only had the O-GPS1 for about 5 weeks by now, but so far, results have been encouraging as this shot at star Vega and surroundings will show:
Pentax K-5 and Tamron Adaptall-2 Model 06B. Stack in Deep Sky Stacker of 3 exposures of 20 seconds at ISO 400
Image contrast enhanced in PhotoImpact. Click on image to see larger version.
Here are 100% crops of the fields indicated:
Alpha Lyra (Vega)
Double Star Epsilon1,2 Lyra
Double star Zeta1,2 Lyra
These test images weren't taken in the best of nights, The almost full Moon was up and there were drifting clouds. Otherwise, I would have boosted both ISO and exposure time. Anyway, I think that starts are neatly round and the double stars, even the rather difficult Zeta Lyra, are clearly split.
And outside the field shown, I even managed to capture this one:
The Ring Nebula, M57 in Lyra. Stack of 5 exposures in DSS. Other details as above.
I mainly bought my O-GPS1 for geotagging but surely, Astrotracer can indeed produce "useful" results too. Don't you think so?
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Forum: Pentax SLR Lens Discussion
09-16-2013, 01:19 AM
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You cannot really - at least as I see things - compare zooms and primes from IQ alone. They are supplementary to each other. And one's arsenal of lenses should reflect one's needs and intended uses.
For me, it is a trivial fact that good primes have better IQ than most good zooms, but also that I may have to pixel-peep or crop very tight to really tell the difference - and further, the versatility of a good zoom may in many situations more than compensate for the need to constantly change primes (and I cannot carry all of my primes in all situations!).
And the flares?
Not much flare here, is there (click on images to see larger versions)?
.JPG)
DA 18-135mm @ 18mm
A bit flare/purple fringing here - but no worse than many a good prime would show in the same situation:
.JPG)
DA 18-135mm @ 36mm
I was waiting at the train station and just had a few minutes to capture these images (plus four more). Without my DA 18-135mm I would probably only have got one.....
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Forum: Troubleshooting and Beginner Help
04-13-2011, 12:18 AM
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As others have pointed out, you have moste likely encountered a problem common with Vivitar lenses with PK-mount. They fit fine on analogue Pentax SLRs, but the flange protecting the diaphragm lever is much too long to fit into a Pentax DSLR. Here's an example with my Series 1 Vivitar 24-48 mm:
Fortunately the solution is simple and straightforward: Loosen the three screws (of which one is pointed at on the picture); lift off the ring with the flange and use a hack saw to reduce the flange to about "normal Pentax size":
No harm done to your lens with that surgery - and no more harm to your camera thereafter !
B.R. / Steen G. B.
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Forum: Pentax SLR Lens Discussion
10-13-2014, 02:13 PM
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Well, here's what mine looks like: 7 contacts on either side.
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Forum: Pentax Q
03-02-2017, 02:24 PM
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I have the Pentax Q adapter and have tried our many lenses of varying focal lengts. Based upon my experiences, I fell pretty safe when I say that the leaf shutter will not solve your issues. With adapted lenses one shuold take into account that
A) Resolution as we would normally perceive it is measured in lines per image height and the 1/2.3" and 1/1.7" sensors of our Qs are actually much more demanding in that respect than an APS-C, let alone an FF sensor. Your Q lenses have been specifically designed for the small sensor format.
B) Your 85 and 135mm lenses effectively serve as very long telephoto lenses on a Q and thus, more sensitive to atmospheric haze and turbulence. Rather than playing with the WB, you should probably try to enhance contrast and clarity using Curves and Levels in the developing/post-processing of your images.
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Forum: Pentax Camera and Field Accessories
05-24-2017, 10:02 AM
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Scorman1 is right: The camera has to detect Altitude and not just Azimuth in order to track properly. Further: The Alt. value is indeed embedded in the Exif-data, and it shoul be easy to display. (In ExifTool, look for "Pitch angle".
My solution is to use an inclinometr app on my smart phone.
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Forum: Pentax Q
04-09-2017, 04:01 AM
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Thank you for encouraging words, barondla. This lens really appeals to be explored - how nice then, that I can have my Q-system with me almost anywhere I go almost all the time.
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Forum: Pentax Q
04-06-2017, 02:12 PM
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Or, rather: I am still exploring/learning how to use this little gem properly. Perhaps a few too many pictures in one post, but you know, I'm like a kid having been let loose in a candy store:
#1
#2
#3
#4
#5
#6
#7
#8 - Strongly cropped
#9 - A good deal cropped
#10
Tamron, many years ago used the slogan "Small but Mighty" about their Adaptall-2 SP 35-80mm CF Macro lens (Model 01A). These words come to my mind while I am playing with the smc Pentax 08 Wide Zoom lens. All pictures were taken with the Pentax Q-S1.
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Forum: Pentax Q
03-29-2017, 05:03 AM
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Thank you all for congratulations and great sample images. I have no doubt that this lens was worth waiting for, and as CarlG says, now the time has come for me to explore!!!
Well, offerings for Q cameras and accessories here in Denmark from serious retailers have been non-existing for a while, and supplies throughout Europe seem to be dwindling rapidly now. So, I have become quite acustomed to self-import Q-stuff from dealers in Japan. After domestic VAT and post office fees for customs handling, there is no financial advantage to that and one further gets the goods without a European Warranty.
But then I saw this 'Special Order' offering on Pentax Q high-performance lenses from SRS Microsystems in the UK - an excellent supplier of a good deal of my Pentax Gear. SRS did warn that there would be an extra delivery time, (B&H Photo has a similar offering currently) but the price was fair, and I jumped. SRS then confirmed the order to me and ordered the lens from Pentax Europe. Pentax Europe then confirmed to SRS and ordered the lens from Pentax Japan......
......anyway, I now have my lens with a valid, European warranty and I think I got it slightly cheaper than if I had imported it myself from Japan.
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Forum: Pentax Q
03-28-2017, 01:46 PM
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I ordered this lens as a 'special order' - and special it was: It took two months and ten days from order to delivery. But now it is finally here to 'complete' my Pentax Q Go-Anywhere Bag:
06 Telephoto Zoom on Pentax Q10; 08 Wide Zoom on Pentax Q-S1; 02 Standard Zoom as in-betweener / back-up; circular polarizing filter,
4 spare batteries; IR remote control; +10D close-up lens and home-made LCD loupe / shade. All in a small bag measuring 23 x 16 X 13 cm.
I think this lens is going to give me much fun. |
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Forum: Photographic Technique
03-07-2017, 06:14 AM
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As others have said: Use SAFE dedicated solar film or SAFE dedicated solar glass filters for the Sun:
.JPG)
With such filters you may get this at 600mm f/11 with ISO = 100 and t = 1/125s:
Pentax K200D with Tamron Adaptall-2 SP 300mm f/5.6 lens and 2X Tamron SP F-Series teleconverter.
Without this filter (Optical Density, D=5) I would have needed an exposure time of 1/125s divided by 100,000!!! Are you sure you got a black rather than a blank image?
Of course, during totality things are very different and you must take off the filter - but ONLY DURING TOTALITY.
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Forum: Pentax Q
02-13-2017, 10:53 AM
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Forum: Pentax Q
02-04-2017, 06:53 PM
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Regarding Q-macro: One other option is the use of a +10D dioptre lens together with the 06 telephoto zoom. A two element multicoated achromat´would of course be optimal, but so far, I have been doing with a cheap Chinese 1-element, uncoated lens. There will often be some purple fringing then, but no more than can easily be handled in post processing.
A good thing with the advanced Q-lenses is that flash can be synchronized down to a /2000s and thus, one can use the flash to freeze movement and hand shake even in broad daylight. Working distance is convenient and the tiny Q-pixels allow for quite some cropping:
Pentax Q-10 image: Mosquito attack (yes, it is my own arm!). Cropped image.
Pentax 06 telephoto zoom @ 24mm FL with +10D close-up lens. Flash on; 1/2000s, f/8.0, ISO 100
Pentax Q-10 image: Cucumber spider, (body is some 2.5mm long). Cropped image.
Pentax 06 telephoto zoom @ 28 mm FL with +10D close-up lens. Flash on; 1/2000s, f/8.0, ISO 100
Regarding the Pentax 02 Standard Zoom: I find it much better that its general reputation. Is this really that bad?:
Pentax Q10 with 02 Standard Zoom @ 15mm FL
Pentax Q10 with 02 Standard Zoom @ 6mm FL.
I like my 02 lens a lot - so much that I have decided NOT to go for the 01 lens. 'Instead' I have placed an order for the 08 Wide Zoom at srs microsystems. It's on 'special order' and the wait is looong - so far 3 weeks since I placed my order.......
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Forum: Pentax Q
02-05-2017, 12:18 PM
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And right you were! I never noticed this section way down the page with Q-lens firmware updates, but I now updated one 02 lens on my Q10 after which it duly shows firmware version 1.01. Inserting the lens in my Q-S1, I now also read the same firmware version here. It so happens that I have two 02 lenses, because I had to take one more copy together with my Q-S1 and that lens still showed Ver. 1.00 on both cameras until I made yet another update with that lens mounted on the camera.
So, monochrome and you were right: The firmware does indeed reside in the lenses.
Thanks a lot barondla, I'd never found this update on my own.
---------- Post added 02-05-17 at 08:29 PM ----------
Hmm..........and now to see what difference this update for "Improved stability for general performance" means to my future 02 images. I never found that I had any issues with the 02 lens as it was.
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Forum: Pentax Q
01-10-2017, 07:15 AM
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On the 2nd of January, I finally got a few hours of clear skies to try out my Q10 attached to a small TS Imaging Star 474mm f/6.78 APO refractor telescope:
2 x 20 images stacked in Registax4; assembeled in Image Composite Editor (ICE); final processing in PhotoImpact X3. 30s exposure time at ISO 1600.
Seeing in the wintertime is worse than lousy from my 4th floor balcony in the midst of a city, surrounded as I am of hot roofs and smoking chimneys, so excuses for the fat, funny looking stars. Still I am very happy to see that the Q10 handles the dynamic range so relatively well.
Now off for some better and darker skies......
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Forum: Pentax K-1 & K-1 II
01-13-2017, 03:42 PM
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So, your image with the most trailing is #1861.
1.I first of all note, that the trailing is for stars all over the frame and thus, we are not talking wide angle field rotation issue.
2. From Phil Harvey's ExifTool I get the following information:
Geographical position:50 deg. 53 min 36s North and 0 deg 12 min 25 s West
GPS date and time taken: 2017-01-12 at 23:20:29 hrs.
Azimuth = 211.94 degrees
Pitch angle (Altitude) = 24.5 degrees
Exposure time = 117.8 seconds.
3. Now, you have conveniently placed Sirius very close to the center of your image so entering date, time and position in Cartes du Ciel (Sky Charts) I can find the actual parameters for Sirius the moment you took your picture. This is the information Cartes du Ciel gives:
Star
HR 2491 HD 48915
Flamsteed Number: 9
Bayer Letter: Alpha
Constellation: Canis Major
Visual Magnitude: -1.46
Color Index: 0.00
Spectral Class: A1Vm
Annual Proper Motion: -0.553 -1.205
SIRIUS; Canicula; Dog Star; Aschere
J2000 RA: 6h45m08.90s DE:-16°42'58.0"
Date RA: 6h45m54.57s DE:-16°44'05.4"
peterh337 2017-1-12 23h20m ( TU + 0h00m )
Sideral Time : 6h50m
Hour Angle : 0h04m
Azimuth :+181°07'
Altitude :+22°24'
Rise : 18h43m Azimuth:+116°23'
Culmination : 23h20m
Set : 3h57m Azimuth:+243°37'
In fact, you have captured Sirius the very moment (almost) it culminated and thus, was due south on that night. So, unless I have made some terrible blunder, your altitude is spot on (Sirius may not be exactly in the center and there is also the atmospheric refraction at low altitudes to consider) but your Azimuth / Compass Heading is some 30 degrees off - and that does explain the trailing that you see across the entire frame over an exposure time of 2 minutes.
As I said in my first post, disturbances or very localised anomalies in Earth's. Magnetic field may spoil your precise calibration, but there may also be other explanations such as a sudden shift in the satellites that your GPS has contact with which wouldrequire a re-calibration.
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Forum: Pentax K-1 & K-1 II
01-13-2017, 04:44 AM
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There is an in-camera physical/mechanical constraint on how long you may track. That is dictated by how much the sensor is actually able to move, and the theoretical upper limit in tracing time then depends upon the focal length of your lens and the declination/altitude of the center point of your image, (: stars near the celestial equator move faster than stars nearer to the poles).
HOWEVER, in prapractise the accuracy of the Astrotracer is very much dependent upon how precise a calibration of your electronic compass that you can actually achive on your specific, geographical location. This is not trivial, because local magnetic anomalies may interfere severely with Earth's magnetic field and thus, confuse Astotracer's compass.
Try different locations, different altitudes and different directions and you may find quite large variations in maximum acceptable tracing times with one and the same lens.
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Forum: General Photography
01-01-2017, 02:38 PM
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I agree with your calculations as far as FoV is concerned.
Whith regards to DoF, your calculations would be correct for systems fulfilling the requirements for camera equivalence. This appears to me to be more subtle, because your two systems (lens + sensor/film) should then provide the same resolution in terms of Lines-per-Image-height. And I am not convinced that one can reliably compute such digital sensor - analogue film comparison on a purely theoretical basis? But as a first approximation, you result should be OK.
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Forum: General Talk
11-29-2016, 03:26 PM
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Got myself a nifty little lens to be shared between my Astro-Macro Pentax Q10 and my Walk-Around Pentax Q-S1:
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.JPG)
TS Imaging Star Astrograph TSED70Q (Ø = 70mm; FL = 474mm; f = 6.78) on Pentax Q-S1 |
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Forum: Pentax Q
09-01-2016, 02:43 PM
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Some shots from this summer with my Q10, Pentax 06 Telephoto Zoom and a +10D close-up lens:
06 lens @ 27.5mm
06 lens @ 29mm
06 lens @ 27.5mm
And oh yes, there were ants in the rhododendron flowers too:
06 lens @ 29mm
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Forum: Photographic Technique
09-28-2016, 03:42 AM
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400mm and f/5.6 isn't entirely 'senseless'. I regularly use my catadioptric 350mm f/5.6 lens together with my K-5 and K-3 plus the O-GPS1/Astrotracer. You just have to realize that accurate calibration becomes ever more important with increasing focal length and you must expect your success rate to drop accordingly. You can see some of my results with various lenses here:
DSLR Astophotography: Astrotracer Images with Pentax GPS Unit O-GPS1
(And note that I have gone up to even 700mm f/11 with some success on rare occasions).
If you are a pixel-peeper and if you go below some 20mm in FL, you will notice that stars become stretched as you move away from the center of your images. This is because Astrotracer can only move in up-down and left-right steps and rotate along the optical camera axis. Thus, unlike a camera mounted on an equatorial platform, Astrotracer cannot ensure that the sensor 'tilts' in order to retain its posistion relative to the position on the celestial sphere where the optical axix was pointing at the beginning of the exposure.
Overall, I should say that Astrotracer works best with lenses in the 24 - 200mm FL range - but do experiment with what you have to gain your own experiences.
If you want nebulae more than Milky Way panoramas (which can be very rewarding in itself) then you do have to consider longer focal lenghts (from, say 135mm and up). Again, please refer to the sample images I have linked to. If you want planetary detail more than Jupiter with its 4 moons as tiny 'dots', then you are in Telescope Land. In all immodesty I can point to my own homepage again:
Camera Settings for Astrophotography
- and whether you are afraid or not, you WILL eventually have to venture into stacking. And it really isn't that 'terrible' after all: Just load your pictures into a program like Deep Sky Stacker; ask the software to do the stacking and then use some sliders to darken/lighten your resulting image until you see your target. After that, you may undoubtedly want to look into the refinements. A starting point could be this tutorial:
Deep Sky Stacker
Have fun with your venture into the many-sided aspects of Pentax DSLR Astrophotography!
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Forum: Mini-Challenges, Games, and Photo Stories
09-20-2016, 12:38 PM
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Great idea with this thread; somehow, the perspective in telephoto landscapes has always fascinated me.
Heatherhill, North Zealand, Denmark: Pentax K200D and Tamron Adaptall-2 SP 300mm /f 5.6 (Model 54B) -an oldtimer from 2011
Hornbaek Harbour, North Zealand, Denmark: Pentax K-3 and Pentax DA* 200mm f/2.8 with HD Pentax-DA 1.4X teleconverter
and with a Pentax Q10 even 45mm become pretty long:
Copenhagen City, Denmark: Pentax Q10 and Pentax 02 Telephoto Zoom @ 45 mm, (taken through the not too clean windows on the 12th floor of the Danish National Hospital)
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Forum: Lens Clubs
09-10-2016, 06:26 PM
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Well, thank you pebberberry farm.
As you have said yourself: There are many uses of the many fine Adaptall-2 lenses out there.
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Forum: Lens Clubs
09-10-2016, 06:12 PM
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Ahaaah......When do we see pictures from that in the Pentax Astrophotography Group?!?
Thank you Marcus, "I am glad thet you asked me that question": I have done a great many lunar and solar photos using a tripod only, but as explained above, stacking is a must for me, meaning that I have had to do a manual alignment of all my images, because Registax can only do a fine-alignment. But very recently I have allowed myself the luxury to by an iOptron SkyTracker, and that has made stacking in Registax a breeze.
Regarding focusing of the 300/5.6 Model 54B that can be done with eyes closed because the infinity stop is spot on with as well my Pentax DSLRs as with the Pentax Q10 and the original Q to K adapter. On the other hand, my 350/5.6 Model 06B focuses past infinity (and accurate focus is exceedingly critical with that lens) so here the solution is liveview with magnification and a modified slide viewer as LCD-hood and -loupe. Also a must-have accessory for Q10 solar photography because otherwise one cannot see a thing on the LCD-screen.
For vibration free shutter release there are many options: Wired or remote programmable release (DSLRs only), IR-remote, 2sec delay (with mirror-up on DSLRs), 3sec delay with IR-release (my remote died yesterday) and finally interval shooting, which is what I use most with the Q10: Just set the number of pictures you want and interval = exposure time + 5 seconds, and the camera does the rest.
Finding and centering one's object on the tiny 1/2.3" sensor of the Q10 is a special challenge, so I have added two more accessories: A n adapted small monocular as finderscope and a Baader Witty1 Tangent assembly for fine adjsutments of the camera shooting direction.
This picture should show it all:
Pentax Q10 with Tamron Adaptall-2 SP 300mm f/5.6 Model 54B on iOptron Skytracker. Here equipped with safe solar filters for day-time sunspot photography
And here's finally a sunspot image taken with my mirror lens but otherwise same setup as above. Not as 'dramatic' as lunar images but quite a challenge to get the contrast right:
Tiny sunspot group on 9 September 2016. 100% non-resized crop. 22 identical exposures stacked in Registax 4-
Pentax Q10 with Tamron Adaptall-2 SP 350mm f/5.6 (Model 06B ) lens and original Pentax Adapter Q for K-mount Lens and Thousand Oaks safe solar filter foil. |
