DigiBorg

Tools

tedishikawa — Thu, 26 Jan 2012 19:21:42 +0000

I brought some tools from my garage. These are not the sophisticated and professional ones at all. But at least they allow to make plain holes,counterbore, tap and cut. If there is someone locally who wish to do one of your plates, please come over my office. I’m not skillful. But if you don’t expect the professional grade, I can do for you. I have to prepare for the steady table first though.

Fluorite Spotting Bino Completed

tedishikawa — Wed, 25 Jan 2012 19:37:22 +0000

This should be the final version as 50mm fluorite spotting bino.

Since it is F8 optics, there is little vignetting. Very compact and good weight balance. Quite easy to carry and walk around in the field. This has become my most favorite spotting scope. This system has capability of binocular-like binoviewing comfort as well as spotting scope-like magnification. Moreover, it creates the clean and sharp image by the fluorite crystal and BORG erecting prism, which allow to push to 100x magnification if wanted. 71FL should be nice too. But Since it is F5.6, 50FL should be just good enough at the view point of the effective aperture and the cost. If someone is looking for high-power terrestrial viewing by both of eyes, I highly recommend this system. This should be the winner (or no competition) in the field since no other brands/optics can do that. I plan to prepare for the complete set.

Canon DSLRs

tedishikawa — Tue, 24 Jan 2012 01:09:33 +0000

As a pioneer of the enhanced-camera provider, we have shipped thousands units all over the world since 1st camera – 300D. Since then, we have 3 options in Canon cameras, which might confuse people. Each option has pros and cons. So I thought I should clarify here since we have same questions all the time. Before describing each option, please note imaging sensor is fairly sensitive from 700nm to 1000nm. I’m not sure the definition of infrared in wavelength. But let me consider this is near infrared(NIR) anyway and refractive optics are not well designed to correct chromatic aberrations. So NIR has to be blocked.

1) Option “T” : This makes things quite simple. It doesn’t require any extra filter since UV/IR blocking filter is already built-in. So this is a ready-to-go kit. But the internal reflections are not avoidable. Bright stars gets larger. Another good thing is this allows to shoot regular daytime shots in custom white balance mode. So this is most economical way. Self-cleaning mode is still functional.

2) Option “E” : This is normally called performance-enhanced since this is the best performer. This camera has no optical filters except CMOS cover glass. Since there is no such interference type of filters, image is cleanest among them. Virtually no internal reflections. So star edge is very clean even in bright stars. But since there is no UV/IR blocking filter, it requires extra filter for refractors and camera lenses. Otherwise image gets softer due to chromatic aberration in NIR region. Setting body-mounted filter is good idea to do so or simply set 2″ UV/IR blocking filter into telescopes. Also this camera allows to shoot UV or IR imaging. Especially ideal for UV imaging than following clear filter option. UV spectrum is considerably attenuated when the light goes through the glass. Minimal glass is advantage for UV. Another issue is no self-cleaning function. No way because of no filters. Fortunately, cover glass looks having the special coating to slip the dust out smoothly. As a real world, this option works well too. This is good for scientific, forensic and nature photographers who are looking for maximum transmission.

3) Option “C” : Clear filter option. We replace two filters with clear ones. Modification process is most difficult because self-cleaning device is re-set on a filter glass. It’s challenging. This is why this option is most expensive. The internal reflection is less than T option but more than E option. It’s good for UV and IR imaging. However, UV is more attenuated because of two pieces of glass. This is the one for people who are concerned about the dust issue. Like option E, it requires an extra filter to block UV or IR for astro and regular shots.

AF is still fully functional in above any of 3 options since all of flange back are set at 44.00mm – Canon specs.

If I’m asked “what is the best options?”, it is still difficult to say. It depends on the budget, the optics you have and simplicity. But I would say option E and body-mounted filter. This combination creates the cleanest image. Yes, Newtonian optics doesn’t need to block IR. So if you have Newtonian telescope, this is it.

Erecting Binoviewing – 2

tedishikawa — Mon, 23 Jan 2012 20:07:32 +0000

I reported my test for erecting binoviewing last time. Here is the update.

This setup uses a regular long tube and reaches focus at the infinity! The custom-adapter was made by PreciseParts to minimize the length. Above configuration is [Drawtube - 7507 - 7364 - BORG Erecting prism - Custom adapter - Baader]. Some eyepieces might not reach focus at the infinity. But in birdviewing application(relatively shorter distance), any eyepieces should be OK. If the shorter tube is used, I’m sure there is no eyepiece restriction at all. My favorite Japanese Ortho (shown in picture) has no problem at all. PreciseParts did great job! Adapter threads are very smooth even in it is metric fine pitch. Generally US machine shops are hesitating to accept the order for metric fine pitch. But PrecisParts is very skillful. I highly recommend if you are looking for the custom adapter. Moreover, cost is very reasonable even if it is one piece. So PrecisParts are very user-friendly machine shop for astro community. As far as I know, this might be 1st attempt with successful result all over the world. Probably BORG is only one which allows for high-power erecting binoviewing. As mentioned last time, yes this setup still makes the vignetting. But unfortunately no way to avoid. But still bright and clean. This is not as compact as binoculars. But this is a kind of high-power binocular, which regular spotting scopes and astronomical telescopes can’t do.

Another 71FL Image

tedishikawa — Fri, 20 Jan 2012 00:01:16 +0000

This is sent by long time BORG user – Sam Saeed.

This is his 1st image taken with a new scope 71FL which was recently upgraded from 60ED. You can take look around his other narrowband wide-field imaging at my blog too. Beautiful, Sam!!

Ha Image by 5D Mark II

tedishikawa — Wed, 18 Jan 2012 19:28:05 +0000

This great image was sent by Charles Banville, Canada.

Image data

Date: December 8, 2011
Objects: North America Nebula and Pelican Nebula
Location: Dominion Astrophysical Observatory, Victoria, BC
Hutech products used: Hutech modified Canon EOS 5D Mark II and Borg 77EDII, f/4.3, with Baader H-Alpha filter
Photographer: Charles Banville (http://rascvic.zenfolio.com/p1064835983)
Exposure info: 31 light frames of 300 seconds, ISO 1600. Light frames were calibrated with dark and flat frames in ImagesPlus.

This astrograph has the built-in filter box, which allows to set and swap various filters without disassembling the system. If you use par-focal filters, you don’t have to re-focus each time. This function should be very useful for one-shot color cameras when Ha frames and regular RGB frames are taken separately. Thanks for sending the image, Charles. Keep enjoying astrophotography with BORG!

My Setup

tedishikawa — Tue, 17 Jan 2012 23:34:55 +0000

One of common questions from customers is how do I set your 71FL astrograph? This is my favorite system. Very rigid and compact.

We plan

1) a new guide scope plate. Unlike the previous plate (KD101 – discontinued), it has the slot which allows for easy adjustment for tube ring separation.

2) new Series 80 tube rings. Unlike BORG-made, there are 1/4″-20 threads at both ends. This makes scope mounting easier without riser blocks. As shown on above picture, current tube rings require riser blocks since one side has plain hole only.

Both items will be available shortly.

Hovering Kingfisher

tedishikawa — Thu, 12 Jan 2012 02:18:14 +0000

These might be kingfisher’s hovering images probably in the unusual high resolution.

BORG 71FL + Pentax K5 by Noboru Nakagawa

Obviously these contrasty color, clean and high resolution images result from the fluorite power and his technique.

White-necked Crane

tedishikawa — Wed, 11 Jan 2012 22:22:58 +0000

This bird looks very sensitive to the human. So definitely we need long focal length. Following pictures were taken from 120m away.

125SD + 7215(1.4x teleconverter ) + E-PL1 by Mr.Matsunaga in Japan

Fuji Will Be Back?

tedishikawa — Sat, 07 Jan 2012 00:46:45 +0000

Fuji’s EXR CMOS looks very interesting design. Basic idea is similar to previous honeycomb concept. Additionally this is back-illuminated type. I was told they plan to announce a new camera at CES next week. Rumor says it’s the mirrorless rangefinder body with APS-C sized sensor. I’m not sure the sensor is the same as EXR CMOS.

http://www.mirrorlessrumors.com/first-image-of-the-fuji-x-pro/

Let’s keep an eye open on Fuji.

I’d like to make the astro test and try to remove the IR-blocking filter as soon as it will be available.

I’m also interested in how Fujinon lenses perform for astrophotography too.

Ted