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Forum: Pentax K-1 & K-1 II
12-15-2023, 03:34 PM
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Oh bed news:(
And I was praying for clear sky so I can test it on my K1-I.
But good that Pentax start to work on issues so quickly, I believe they can handle it.
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Forum: Pentax DSLR Discussion
12-15-2023, 02:58 PM
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I didn't own a DFA*50/f1.4. but there is review about it astro-performance, here is link: Account Suspended
For some reason now I can't open it, maybe problem on my side.
As I remember from review lens has some amount of chromatic aberrations and coma and Astigmatism were gone only when it was stoped to f2.8!!! That's 4 time less light then at f1.4 which. For a lense which cost 1299 euro it's disappointing performance. Because "cheap" HD PENTAX-FA 50mm F1.4 which cost 399 euro at f2.8 perform same as lense which on 900 more expensive and both lenses are bed on faster f number.
Regarding Pentax 70-200 mm f2.8 I don't have it, but I have Tamron 70-200 f2.8 which if rumors are true is a same lense but without weather sealing but optics is same.
Tamron is quite good for astro at 200mm. You will found Pleiades I shout with it in my profile.
---------- Post added 15-12-23 at 22:17 ----------
Don't be to fast on decisions.
If you plant to shoot at APC-S then Sigma Art 18-35mm F1.8 one of options to consider. At APC-S it is usable at f2.2 but I'm kind of "pixelpiper"...
I also recommend to think of Irix 30 mm f1.4. yes it's manual lens but it has weather sealing. I will post a review for this lens soon on this forum, review for astro. If very shortly for Pentax K mount this is best lens in 30mm focal length, I had a bed luck with 1st two copies of lens. Its not absolutely perfect but a very strong option in my opinion.
Regarding focusing one more hint, if you use basic method of "star shape minimizing" I recommend point a camera on constellation shape of which you know well and which have enough of relatively bright and dim stars, for example Cassiopeia. When you will start to focus at first visible will be only bright starts but when you are in focus you will start to see dim starts as well. I hope I explained well enough and you understood the idea.
Good luck)
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Forum: Pentax DSLR Discussion
12-15-2023, 02:15 PM
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I'm not surprised that lense is my top1 of the worst Pentax lenses for astro a specially at FF. Extreme coma and bed manual focus...even worse then on 35mm f2.0.
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Forum: Pentax DSLR Discussion
12-15-2023, 02:03 PM
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Hello, I know you pain.
I did next to ensure I reach best possible focus on my Pentax K1-mk1:
1) Wheel set to manual exposure.
2) ISO 6400, shutter speed 3 sec(must be 2.98 to avoid stars movement for 100%). For you calculation says 2.95 so 3 sec should be also OK.
3) Then I switch to 1.5 crop instead of FF and use live view.
4) Put Jupiter in center of frame(any other bright enough start is good).
5) Zoom to x16 in live view, put Bahitov mask Infront of lense.
6) Adjusted to perfect focus( middle line should be centered between side lines) if this say nothing to you watch YouTube video about Bahitov mask.
7) Took a shot with IR-remote to avoid vibrations.
8) Evaluated picture taken with Bahitov mask, and adjusted focus in case middle line not perfectly centered.
9) Stick a tape on lense to fix the focus ring.
10) Repeated step 7 and 8 to be sure focus not shifted.
11) Switched to FF.
Focus is adjusted. In your case you have APS-C so I don't think you can crop in camera more... I used crop so that stars looked bigger in live view and I can easier use Bahitov mask... Cause 35 mm is well let's say challenging for Bahitov mask.
By the way I bought 35mmF2 lense as brand new from official Pentax store in Czech Republic and tested for one week. On different f stops from f2 to f3.5.
After one week of testing I returned it because of:
- infinity focus has a hard stop.
- it has very "short" rotation length for manual focus... Very hard to be precise.
- sharpness level not enough for astro.
- image quality in aspect of astrophotography(Chromatic aberration, Coma, Astigmatism, Vignetting) for a Pentax lense is quit good.
- If I compare it to similar focal length from Rokinon, Irix or Sigma, Pentax is the worst for astro.
I think you can't reach much better results with this lense, but you can try to get better focus with method I described. At the end it's you only yours decision if you satisfied with lense or you want better.
Short off topic. This is really difficult situation.
Pentax cameras like K1-x, KP, K70, K3-x (if not look on fixed screen) are absolutely amazing astro cameras.
But when comes to optics for astro, well basically in almost all focal lengths optics from Pentax is worth then 3rd party lenses a specially on FF, just no chance...
I think this is because of ideology of optics designers at Pentax, all the time they are trying to build lenses which will render artistic image, emotional image.
Unfortunately for astrophotography you need that lens will be as fast as possible and corrected for all aberrations as perfect as possible.
So totally opposite to rendering artistics image...
P.S.: on lenstip.com you can find reviews of lenses and look how their perform in coma, astigmatism and CA. So far the best source of data for astro I found.
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Forum: Pentax DSLR Discussion
03-27-2023, 01:41 PM
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Hello, I think you already get a good advice which will help to make your decision.
But I will try to take a summary:
- K70 & KP both are discontinued, but K70 is still could be found as new one in online shops and with good price drop.
- K70 replaced by KF but it's value for money is very questionble... It's overpriced in my opinion.
- K-70 is very user-friendly camera, fully articulated screen is really strong point. Most modern webs/app resources for file share are optimized for vertical orientation, for KP this is week point.
- Both cameras need external GPS unit, external GPS much easier to calibrated for Astrotracer a specialy for longer focal length, so I would not consider Pentax cameras with build in GPS module if you plan to use lenses longer then 85mm, (I owned K70 and now K1-I and really know the difference).
- K70 very light camera and compact good for hiking and for shooting and distant "wild" locations without light pollution.
- KP has a bit better SNR and better dynamic range, but not so much better.
- K70 has a possibility of dummy battery which, has just a body of batter and USB cable which is by connection to a powerbank makes basicly unlimited battery life I didn't found such a think for KP.
I personally loved my K-70, but I bought it used and it failed in year and half. It wasn't solenoid issue but some issues with PCB which was expensive to repair instead of it I decided to take a K1-I as in general it looks like best astrophotography camera of all times not because of some 1 unique feature it has but due to all features it has (that just my subjective opinion...).
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Forum: Pentax K-70 & KF
03-14-2023, 04:56 PM
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I have used my Sigma on K-70 and on K1-I (in FF mode from 28-35mm with small cropping in post). I didn't have any problem with AF in both cases.
There is a lot of stories about problem with AF with this lens at Pentax bodies, my personal experience do not confirm those stories.
What I have to highlight that when I start to use lens with K1 at beginning I had problems with AF, but it was my wrong setup of camera. As soon as I understood it, I had no problems.
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Forum: Pentax K-1 & K-1 II
03-10-2023, 02:34 AM
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Direct. Person is asking how to activate 1/3 and 2/3 stops. I'm explaining that he or she don't need at all. In future it could cause problems with noise, colors, details. It better to avoid some not optimal setups then to get used to it and then with time to start learn how to do it right.
---------- Post added 10-03-23 at 10:47 ----------
Yes and every one can check this by his own, even at home in dark room at night. Take a shots with different ISO and all the rest leave same, then equalize exposure of all photos in PP and compare the results, you will see the difference.
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Forum: Pentax K-1 & K-1 II
03-09-2023, 01:41 PM
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Probably you do only day time photography, it's a luxury when you have so much light that you can make photos with 1/xyz of a second... Try make photos in light condition when you need 10+ seconds and photo is still underexposed.
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Forum: Pentax K-1 & K-1 II
03-09-2023, 09:31 AM
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If will take account for base iso, then full stops and half stops is a 1st scaling.
But 1/3 and 2/3 stops a scaling from already scaled.
---------- Post added 09-03-23 at 17:48 ----------
Both statements are common misconceptions. Because same sensor in different cameras could and will have different "behavior". Camera it's not only about sensor, it's much more complex device. The "neighbors" of sensor affects the result. Sensor placed on some circuit board, it has some specific voltage supply, different analog amplifier, different ADC(Analog to Digital Converter), different digital amplification. Even same microchips used could have different firmware revision and so on...
Each manufacturer uses his own "chemistry" even if sensor is same.
Why do you think K1 and K1-II shows different results with same sensor?)))
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Forum: Pentax K-1 & K-1 II
03-09-2023, 05:19 AM
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I would say, stay away from it. Use only full stop and half stop ISO.
When camera offer steps of 1/3 to change the ISO setting. The camera is scaling images to mimic these ISO settings. For 1/3 stops, like ISO 125, the camera will simply use the analog amplification of ISO 100 and scale it digitally to match ISO 125. On the other hand, for a 2/3 stop like ISO 160, the camera will use the next ISO setting and scale it back down.
Therefore use the ‘real/true’ ISO stops: 100, 200, 400, 800, 1600, 3200, etc.
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Forum: Post Your Photos!
12-30-2022, 12:14 PM
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thanks
---------- Post added 30-12-22 at 19:16 ----------
thanks, yes without clouds it would be boring.
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Forum: Post Your Photos!
12-06-2022, 01:21 PM
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I was hiking in Dolomites area in Italy, it was raining... I came out form wood and was crossing the field, suddenly sunlight made this nice light effect on mountains which were few km from place I was.
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Forum: Pentax SLR Lens Discussion
12-03-2022, 01:39 AM
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Forum: Pentax SLR Lens Discussion
11-28-2022, 12:58 AM
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Forum: Pentax SLR Lens Discussion
11-27-2022, 02:20 PM
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For day time it perfect lens.
For astro everything depends from your requirements, if you are fine with aperture 2.8+ and you don't care about star shapes in corners then it's fine, you can crop the image...
If you are more strick to IQ, if you do some prints for sale, then I think it's not the best lens.
BTW, svět je těsný)
---------- Post added 11-27-22 at 02:29 PM ----------
Irix 15mm f2.4 looks like has no competition at FF for K mount, not only because optical quality.
But other useful staff: sealing, focus lock, infinity calibration on lens, tactile feeling when infinity reached. Last one is really useful.
Today I had time to make few shots with Sigma 18-35mm at Pentax K1. I will share few image examples after I finish editing.
In general for APS-C you will not find any better for K-mount.
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Forum: Pentax SLR Lens Discussion
11-27-2022, 12:11 PM
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sure, modern lens with cost over $1,000 is good or very good during daytime photography. It would be unforgivable if it wasn't.
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Forum: Pentax SLR Lens Discussion
11-27-2022, 07:49 AM
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I'm using Irix 15mm f2.4 and Rokinon 24mm f1.4 and Sigma 18-35, but on FF it usable from 24mm(very small crop needed).
Irix 15mmf2.4 is really good lens for astro. Not the fastest but fast enough and on FF it's wide, maybe even too wide:)
Rokinon 24mmf1.4 usable from f2.5, probably not best copy...
About sigma I already wrote.
I also own Takumar 200mm F4 in M42 mount. Very flat field, nice star shapes, only CA is makeing a bit of problem and slow f-number. But for its money it's excellent.
Now I'm going to buy again 21mm f1.4 from Irix, with 1st copy I had a bed luck. I'm waiting for clear sky without clouds and moon... To test it...
I would be happy to spend my money for something good for astro(fast and no aberrations) from Pentax. But it's not available in my opinion... They have *85mm f1.4 and *50mm f1.4 need to be stoped down to get good results, but then I don't see a reason to pay so much if they starting to be good from f2.8. For wide field I think there is nothing at all. All those 16-50, 11-18 are f2.8 and you need to stop down them.
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Forum: Pentax News and Rumors
11-27-2022, 04:47 AM
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What is meant under include EXIF data? I should somehow separately upload them or what? Or its enough if EXIF in available inside JPEG file and available to access in any viewer.
thank for reply.
Sorry for a stupid, question, new member to forum...
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Forum: Pentax SLR Lens Discussion
11-27-2022, 03:36 AM
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I have this lense, I would say it's quite good performer. It's not the best of best lens in AF speed but not so bed as it's described here on forum. I use it at K1 and K-70. I think this lens limited by bodies... Maybe on K3-III it will be better.
What I do not like at this lens it's coma and astigmatism and CA in astrophotography. I think it should be better for that money... I shoot mostly astrophotography and I'm a bit picky to aberrations.
But in general for APS-C it's best what you can find for Pentax. List of modern limited lenses is short, it's sad.
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Forum: Welcomes and Introductions
11-24-2022, 05:19 AM
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Thanks, you should give it a try. For me it's very relaxing and pleasant time. Now its a good time for it, night starts very early. But be careful this good be very expensive and time consuming if you will go with road of heavy scopes, dedicated cameras and so on... Try to keep it simple.
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Forum: Welcomes and Introductions
11-23-2022, 01:11 PM
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Thanks for info, for today it's too late. But tomorrow will make a review for one very new 3rd party lense for K mount, which so far not reviewed here.
---------- Post added 11-23-22 at 02:05 PM ----------
Oops, sure and sorry.
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Forum: Welcomes and Introductions
11-23-2022, 01:08 PM
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Díky, mám se fajn:) co ty?
Translation: Thanks, I'm fine :) how about you?
Moderator note: reminder, everyone, English only please.
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Forum: Welcomes and Introductions
11-23-2022, 11:15 AM
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Hello to All from Czech Republic:)
I'm in love with astrophotography with help of Astrotracer from Pentax.
I like to keep things simple, therefore NO mounts, startrackers and havy scopes with guide scopes, calibration frames and so on.
I do like to capture some deep space objects, but also like to take some wider shots with simple lightpainting, examples attached.
M45, taken on K1 mk1 with Tamron70-200mm at 200mm@f2.8, ISO800 20 sec, 4 hours total exposure time.
Andromeda was taken on K-70 with Takumar 200mm at f4 ISO6400 20 sec, 30min total exposure time, no calibration frames.
3rd photo taken on K70 and Rokinon 10mm, this is one of my very first astro photos from 2020.
4th, recent one with K1 and Irix 15mm, Sky: 5x60 sec. @f2.4 ISO 1600. Foreground 30 sec, @f5.6 ISO 3200 lightpainted.
Regards,
Andrii.
P.S.:
I planned to earn some good karma with my 1st post in Thread - The Great Astro Lens Test, cause I have a lot of test picture, but for some reason cant post there, no idea why:(
my ig account - an.kuli.
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