> For the complete documentation index, see [llms.txt](https://docs.sevenpens.com/drawtab/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.sevenpens.com/drawtab/guides/pen-displays/ag-sparkle.md). # Anti-glare sparkle ## Overview Anti-glare sparkle is a side-effect of the anti-glare treatment applied to your pen display. How much AG sparkle is visible depends on a lot of factors. Generally, people want very low amounts of AG sparkle. {% hint style="info" %} If you are looking into removing or reducing the amount of AG sparkle, go here: [Reducing Anti-glare sparkle](/drawtab/guides/pen-displays/reducing-ag-sparkle.md) {% endhint %} ## Companion video Because this is a visible phenomenon, watching the video I made on this topic may be a good starting point. {% embed url="" %} ## How it works To prevent reflections and room lighting from interfering with your drawing experience, manufacturers of pen displays provide an anti-glare treatment. The treatment comes in two forms: * anti-glare etched glass * anti-glare film The physics of the anti-glare treatment produces an effect called **anti-glare sparkle** (AG sparkle). AG sparkle is hard to describe in words, but overall it looks grainy. ## What it looks like Photographing it or filming it is very tricky. Depending on the camera settings... * the effect can disappear * the sparkle can look very different from what your eyes see. * you might notice it more with some colors than others ### Example 1 The pictures below show screens displaying black, white, and gray pixels. The one on the right represents a more extreme example. You can clearly see the different "color grains."
### Example 2 It could also look like this — this is a very close-up view.
### Example 3 I found this in a reddit post. The AG sparkle is everywhere but is most noticeable in the green area. ![](/files/jWGHWTqFVxugXNb14nrg) ## How manufacturers refer to the AG treatment **Huion Kamvas Pro 24 (4K) \[GT2401]** **XP-Pen Artist Pro 16TP \[MD160U]** ![](/files/DIqTDKB9ebd57UUJcm3R) **Wacom One \[DTC133]** ![](/files/vUfE3LAgNrdEQZm5bjh9) ## Buying a tablet You MUST research AG sparkle for any tablet you intend to buy. I see many people buy tablets and not realize AG sparkle might be present. Then they get very frustrated with their purchase. DO NOT rely on photos provided by the manufacturer. These photos never show AG sparkle. It's probably not even deliberate that AG sparkle isn't shown because it is very tricky to photograph. You need to ask people who use the tablet if the tablet exhibits the effect and how much the effect is visible. ## Prevalence AG sparkle varies depending on the pen display model. All pen displays that I know of will have some amount of it because they all have some kind of anti-glare treatment. ## Contributing factors Your perception of AG sparkle will be affected by several factors. * The nature of the anti-glare treatment. Some tablet models seem to use a very intense AG treatment, while others have a much milder treatment. * The distance between your eyes and the tablet. What might be strongly noticeable at a few inches away might be essentially invisible at a normal drawing distance. * The pixels-per-inch (PPI) of the display. ## High Pitch (PPI) displays High-pitch means lots of pixels per inch (PPI). For example: * 4K on a 27" pen display has a pitch of 163.7 PPI * 4K on 16" pen display gives a pitch of 281.4 PPI AG Sparkle will appear more on high-pitch displays If the same exact AG treatment is used on those two displays you will notice it more on the 16" display. ## Reddit threads * r/huion - - This deleted Reddit post has a video that perfectly demonstrates the shimmering effect of the sparkle. * r/huion - [Is this normal? Possible display issue? noisy output?](https://www.reddit.com/r/huion/comments/z2gfsx/is_this_normal_possible_display_issue_noisy_output/) 11/23/2022 ## References * [Radiant Vision Systems - Repeatable Sparkle Measurement for Quality Control of Anti-Glare Displays](https://www.radiantvisionsystems.com/blog/repeatable-sparkle-measurement-quality-control-anti-glare-displays) 2020-10-26 * [Radiant Vision Systems - Defining a Sparkle Measurement Standard for Quality Control of Anti-Glare Displays](https://www.youtube.com/watch?v=8iTGUNAxPOc) 2020-10-08 * [Gollier et al. - Display Sparkle Measurement and Human Response](https://jamesferwerda.com/wp-content/uploads/2015/06/r23_gollier13_sid.pdf) * [Ferwerda et al. - Perception of sparkle in anti-glare display screens](https://jamesferwerda.com/wp-content/uploads/2015/06/j18_ferwerda14_jsid.pdf) --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.sevenpens.com/drawtab/guides/pen-displays/ag-sparkle.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.