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ULT-700D Complete Kit (Deep cooled Canon 700D)

JTW Astronomy Cooled DSLR

Announcement 19.04.15 - No more assembly!

We no longer are assembling these cameras, only kits are available now for a much lower price. These are available to anyone, so if you are good with your hands please get in touch. Your local camera modification service can also put one together for you. We made this decision as we find ourselves focusing more on engineering/production and sub-contracting of telescopes and mounts.

The Best Cooled DSLR System Available!

This camera represents the pinnacle of modified DSLR cameras. Deep cooled to 80C below the the sensor's normal operating temperature. This camera is 4x more sensitive than a regular DSLR and is capable of exposures of one hour in length without breaking a sweat. This is not only a great one shot colour camera, ideal for the short imaging windows allowed with the European climate. It is also perfectly capable of taking extremely long narrowband exposures.

All ULT images on this page are credited to Dr F. Hemmerich. These images were taken either with monochrome or colour ULT series cameras.

Cooled Canon 700D

New Features!

  • Set point cooling - power consumption as low as 750mA
  • Argon gas filling
  • Sealed for life
  • Hutech and Astronomik Filters supported

When people think of the sensitivity of a DSLR, the preconception is that it is much less than a CCD sensor. This is not the case. First of all, the losses with a standard DSLR are before the photons even reach the sensor. The standard filters in the camera stop 75% of the light at the h-alpha line. We remove all the filters from the donor camera, the so called full spectrum modification. This gives a 75% increase in apparent sensitivity, as 4x more light is reaching the sensor. Comparing common sensors yields even more interesting facts. A DSLR sensor has a quantum efficiency of around 25-35% depending on how good it is. Quantum efficiency is the chance that an incident photon will generate a photo-electron, basically a CMOS sensor will register about 1/3rd of the photons that hit it. Comparing this to a standard CCD sensor which has a quantum efficiency of 40-60% you can see it is not far behind, and only a fraction of the cost. There is also the advantage of much less noise, so you do not need to stack so many images for a satisfactory result.

Cooled DSLR compared to CCD camera

While it is true that CCD is superior in terms of raw sensitivity (when comparing similar systems!), it doesn't always make much sense to pay all that money for one. Most objects imaged by amateurs are not that demanding on hardware. A one-shot-colour camera really excels when you have short imaging sessions due to weather or a lack of free time. The low noise levels and increased sensitivity from the Astro-conversion mean that you can image an object in one session. We can also remove the bayer matrix if required, and convert the camera to a monochrome CMOS system, giving a massive boost to resolution and sensitivity.

DSLR Noise comparison

This camera has a multi purpose adapter system. It can connect to regular telelenses as well as T2 telescope equipment. The camera itself has a tripod thread and you can use clip-in filters (such as Hutech and Astronomik), 2" filters can also be accommodated on special request. With the telescope adapter in place you can connect directly to your scope using clip in filters or use a filter wheel. We do not think there is a system out there like ours, with all this functionality in one adapter.

Cooled DSLR Running man

Perhaps the most useful improvement to our Ultimate system is the addition of setpoint cooling. This is a simple self contained system, no control box, no microcontroller, just a dial on the back of the camera. The cooling is regulated by PWM, the duty cycle is from 15% to 85%. After two years of feedback from customers with many different cameras on many different systems we have found the sweet spot for DSLR imaging to be around -15 to -20C. The benefits of such a large cooling system now are like the benefits of a large engine on the motorway. Just set the dial and the system will lazily hold the camera at -15C even on a hot day. Resulting in significant power reduction. Indeed so much so, this new camera has rendered our ECO series cameras obsolete and we have pulled them from sale.

M31 - JTW Astronomy - Cooled DLSR

One of the benefits of buying directly from a manufacturer, besides supporting European industry, is that you can customise your camera system exactly to your requirements. Custom anodising, custom hardware, custom finishes, even hydrodipping. Below are two of our favourites.

Horsehead and flame nebula via cooled DSLR Horsehead and flame nebula via cooled DSLR

As with all our products, we spare no expense in delivering the best there is to offer. We cut no corners, everything from the aerospace grade aluminium chassis, to the intricate heatsink, the ferocious TEC cooler, hi-tech ceramic heat transfer compound right down to the last nut and bolt. The entire system is built to do one thing, and do it very well. There is no other camera on the planet that will do the job quite like ours. These benefits are even more powerful, as we designed our camera for the best performance in the real world. Not a bench test. The camera comes with a 2 year warranty on the Canon donor camera, and a 3 year warranty on all our systems.

Backyard EOS - JTW Astronomy - Cooled DLSR

Every camera comes with full copy of the highly acclaimed and feature packed Backyard EOS DSLR control software to enable you to take full advantage of your JTW Ultimate series cooled DSLR camera. Take a look at the features here - User Guide. Due to the camera being stripped to the bones, all functionality is handled by your computer. Exposures of any length can be accomodated and the images are directly downloaded to your computer. This flexibility combined with the camera's complete overhaul gives you a great astronomical instrument with a huge, sensitive sensor for a fraction of the price of a CCD camera. The camera retains all useable functions such as LiveView, which makes focusing and framing your shot easier than ever.

Backyard EOS - JTW Astronomy - Cooled DLSR

The JTW Ultimate comes ready to connect to any system out there. Installation of various filters can also be accomodated during the building phase, such as narrowband or light pollution filters. We can also send the donor camera away to a specialist to have the CMOS sensor physically debayered, resulting in a true monochrome cooled DSLR camera, the camera sensor is already receiving 4x as many photons at the h-alpha line. By removing the bayer filter we are allowing this light to hit 4x as many pixels too! This is a massive boost in sensitivity & resolution.

Backyard EOS - JTW Astronomy - Cooled DLSR

Here are the key features of the JTW Ultimate series of cooled DSLR cameras

  • Built around the new Canon 700D camera
  • Real world performance
  • Setpoint cooling
  • Lens Drive
  • Can connect to any system out there
  • CCD-like performance for a fraction of the price
  • Large APS-C sensor size for a fraction of the cost of a similar CCD sensor
  • Full licensed copy of the market leading Backyard EOS software
  • Individually hand built to international norms
  • Powerful over-engineered cooling system guarantees noiseless operation in any climate
  • Hand lapped aluminium cold finger gives homogeneous cooling over the entire area of the sensor
  • Insulated cold finger ensures efficient cooling on the target area, also allows the rest of the camera to safely remain at ambient temperature
  • Ceramic heat transfer compound used instead of standard thermal grease, offers 30% better performance
  • Computer designed housing guarantees minimum weight, while still giving the benefits of a metal housing
  • Lightweight yet incredibly tough CNC machined 7075 aerospace grade aluminium housing with integrated cooling system
  • A durable foam lined impact proof case to protect your investment is available at a discounted price
  • Software for complete computer based operation of your camera provided free of charge
  • Every camera is unique, you even can specify your own colour of anodising, as well as custom engraving
Debayered monochrome cooled DSLR

All cameras are offered with a 30-day no questions asked return policy. We provide complete systems, including, software, cables and detailed instructions. You also receive free access to software and driver updates for life.


  • 17.9MP Hybrid CMOS Sensor, pixel size: 4.3m x 4.3m
  • 22.2 x 14.9 mm colour CMOS sensor
  • low-pass & IR/antialiasing filters removed
  • ISO 100 - 12800
  • Image format: RAW (CR2 14bit), JPEG
  • 1280 x 720 (720p, 16:9) @ 30/25 fps
  • DIGIC 5 Processor
  • Live view mode
  • USB 2.0 interface
  • 80W Regulated
  • Backyard EOS, EOS utility
  • Dimensions: 155x90x105mm
  • Weight: 900g
  • 3 Year Warranty
Backyard EOS - JTW Astronomy - Cooled DLSR

Delivery Schedule

Please email in for ordering information.


Model Cooling Sensor type Power consumption Operating Temperature Price
ULT-700D Two stage peltier Colour Digital setpoint 70W Delta T = -85C 659,99
ULT-700DM Two stage peltier Monochrome Digital setpoint 70W Delta T = -85C 659,99

Module Pricing

Item Description Price
Main housing Finished CNC parts 169,99
Rear housing Finished CNC parts 19,99
Heatsink housing Finished CNC parts 39,99
Electronics assembly Cooling/USB interface 134,99
Peltier Two stage 90,99
Heatsink housing Finished CNC parts 49,99
Front end Lens/telescope interface 34,99
Window AR window to camera 29,99
PSU & Cables Complete set 24,95
Desiccant 3D printed holder 12,49
Heatsink Complete 29,99
O-ring set Complete set 9,99
Bolting Complete set 4,99
Special tools Set for assembly 30,99

Prices are excluding BTW (VAT) at 21%

The JTW Ultimate cooling system and associated electronics are patent pending, protected to the full extent of the law. All rights are reserved.
JTW Astronomy 2011-2015