ASI533 - "1 inch sensor" is NOT 1 inch! @ZWO, please, correct misleading info.

Obs30

The diagonal of the ASI533 sensor is 16 mm. That is 0.63", less than ⅔ inch! Not 1 inch.

The edge length is 11.31 mm. That is about 0.45 inch, less than ½ inch! Not 1 inch.

The drawings and the advertising is talking about 1" square or 1" diagonal. One inch is 25.4 mm. Both statements are completely wrong!

This is due to a historic marketing from Sony and Nikon, which was originally meant for vacuum glass based sensor, where the glass tube was 1" square, but the sensor's active area was as well only 16 mm in the diagonal.

I am very surprised that ZWO sticks to this very wrong and strongly misleading information on their ASI533 advertising and data sheet.

ImNewHere

The 1 inch isn't actually the sensor measurement, but the sensor size and it is based on the measurement of a video camera tube, and that stuck for some reason once digital sensors came on the scene. Here's a table of them and it is weird, but it is what it is.

https://en.wikipedia.org/wiki/Image_sensor_format#Table_of_sensor_formats_and_sizes

So, yes, it is a 1" sensor, but that is because of how digital imaging sensors are classified, which has nothing to do with the actual physical measurement matching the sensor "size"

Tech@ZWO

ImNewHere is correct, this is commonly used in the industry.

Obs30

Thanks for the historical details, which are all well known. One more reason to correct it.

Check out the drawings and ads on the ASI533 ZWO product page. They clearly and falsely show wrong dimensions on the drawings and the pictures. Actually, it is a mix of correct edge lengths and wrong diagonal. The main ad states 1” square size. It cannot get more wrong like this in a technical fluent community.

w7ay

Obs30 The main ad states 1” square size.

Yep, the drawing is definitely not just misleading, but false advertisment.

The one inch has to do with the diameter of the glass vidicon tube, not the diagonal of the detector area.

Chen

Obs30

Thank you, Chen!

Obs30

Corsair Thank you for all the links and comparisons! Very helpful.

ZWO seems to be the only company in that list that actually claims IN THE PRODUCT DRAWING (see Chen’s post above) that the diagonal measures 1”. Please, just update and correct those drawings… no biggy.

I think so, too, it is way overdue to get rid of the 1”-reference to a 16 mm diagonal… I wonder what the response would be in this forum if ZWO would call the ASI533 a “25.4 mm square sensor” 😉 ?!

Tech@ZWO , please, don’t get me wrong! I love the ZWO products and just received the FF130mm astrograph. The most amazing telescope I ever owned, looked through and which creates amazing astro images.

I am also in a constant discussion (for 2 years now) with Avalon Instruments to make their Raspberry-Pi-based mount computer/driver fully compatible with the ASIAIR, which they just don’t do… for whatever technical or lack-of-ressources-related reason.

So, I am all pro ASI products as you can see… that’s why it bothers me even more to see such technical capable people to adhere to such wrong statements.

Obs30

While it is correct that the 16mm-diagonal sensor is called 1“-sensors, your drawings are wrong and this is in fact false advertising.

How do you want your clients to interpret this info?
It comes down to credibility and technically correct product info.

Corsair

This is an industry standard issue. The whole industry needs to change.

ZWO: https://astronomy-imaging-camera.com/product/asi533mc-pro-color/

QHY: https://www.qhyccd.com/astronomical-camera-qhy533/

Player One: https://player-one-astronomy.com/product/saturn-c-sqr-usb3-0-color-camera-imx533/
https://player-one-astronomy.com/product/ares-c-pro-usb3-0-color-camera-imx533/

RisingCam: https://www.aliexpress.com/item/4001359842748.html

However - maybe it is just a matter of not even mentioning that particular metric anymore.

For example - Altair: https://www.altairastro.com/altair-hypercam-533c-colour-camera-9239-p.asp

Tech@ZWO

Obs30 Thank you very much for your support.
But we are not the only one, it is the industry standard. And Sony claims IMX533 as a 1" sensor as well.

Obs30

Tech@ZWO Sorry, to disagree … again.
It is one thing to call it a 1” format sensor (which is kind of correct for whatever historical reasons), but a completely different and wrong thing to claim in the drawing the actual dimension is 25.4 mm (= one inch) in the diagonal.

Especially, when in your table you are writing that the diagonal is only 16mm. So your drawing is completely wrong, you claim a different size than in the spec sheet and on top of it, you are not only fully aware of it, but also you do not seem to have a problem with it, either.

Searching the Sony website, I could not find any reference to a 25.4 mm diagonal for the 1” format chip.

Obs30

Here you go. The Sony spec sheet for the IMX533 sensor.

Sony calls it the Type 1 format now. No more mentioning of 1” format.

15.968 mm diagonal for the effective imaging area. Not 25.4 mm.

https://www.sony-semicon.com/files/62/flyer_industry/IMX533CLK_Flyer.pdf

And here the specs from your webpage claiming 25.4 mm diagonal. Which is wrong

Tech@ZWO

Obs30 Got it, i forwarded this to our team.
Thank you for your feedback.

Obs30

Tech@ZWO Thank you!

Obs30

It has been two weeks and the drawings in the product descriptions are still wrong...

https://astronomy-imaging-camera.com/product/asi533mm-pro/

Imagining now, I would buy this camera and after first use, I would notice the chip size is completely different and much smaller than advertised and the provided drawing from your webpage... how would your customer service and marketing defend and correct this?

Tech@ZWO

Obs30 I confirmed with our team, that they are working on it, will adjust it very soon.

Obs30

Thanks! Appreciated!

Albirphil49

I notice zwo now say it's a Type 1 ,this really dose not clear things up but to some just clouds the issue.Now if it was advertised as having a 16.5 (half inch )clear aperture sensor,as is done with telescope's we would know what we are actually buying.

KC_Astro_Mutt

Sony describes the sensor as Type 1. Also, 16.5mm is not 1/2 inch.

Albirphil49

KC_Astro_Mutt ok half inch or not it definitely is not 1inch as is shown in the tec info.By the way what is 16.5 mm in imperial measurements.

w7ay

Albirphil49 By the way what is 16.5 mm in imperial measurements.

Divide by 25.4 mm/inch?

Chen